A  CASE  OF  MENDELIAN  INHERITANCE  COMPLICATED 

BY  HETEROGAMETISM  AND  MUTATION  IN 

OENOTHERA  PRAT  IN  COL  A 


BY 

FRIEDA  COBB 


A  DISSERTATION  SUBMITTED  IN  PARTIAL  FULFILLMENT  OF  THE  REQUIRE- 
MENTS FOR  THE  DEGREE  OF  DOCTOR  OF  PHILOSOPHY  AT 
THE  UNIVERSITY  OF  MICHIGAN 


1921 


A  CASE  OF  MENDELIAN  INHERITANCE  COMPLICATED 

BY  HETEROGAMETISM  AND  MUTATION  IN 

OENOTHERA  PRATINCOLA 


BY 

FRIEDA  COBB 


A  DISSERTATION  SUBMITTED  IN  PARTIAL  FULFILLMENT  OF  THE  REQUIRE- 
MENTS FOR  THE  DEGREE  OF  DOCTOR  OF  PHILOSOPHY  AT 
THE  UNIVERSITY  OF  MICHIGAN 


1921 


BIOLOG1R 
R 


A  CASE  OF  MENDELIAN  INHERITANCE   COMPLICATED   BY 
HETEROGAMETISM  AND  MUTATION  IN  OENOTHERA 

PRATINCOLA1 

FRIEDA  COBB 

University  of  Michigan,  Ann  Arbor,  Michigan 
Received  June  21,  1920 

TABLE    OF    CONTENTS 

INTRODUCTION 1 

Hypothesis  of  heterogametism 2 

Equivalence,  within  strain  C,  of  pollen  of  Oenothera  pratincola  f.  typica  and  mut.  latifolia. .  4 
The  F3  and  F4  generations  of  the  cross  mut.  formosa  from  strain  E  X  mut.  latifolia  from 

strain  C 5 

The  FI  and  F2  generations  of  the  cross  f .  typica  strain  C  X  mut.  formosa  strain  E 6 

The  FI  and  F2  generations  of  the  cross  mut.  formosa  strain  E  X  f .  typica  strain  E 7 

The  FI  and  F2  generations  of  various  crosses  between  f .  typica  M  (the  new  Mendelian  strain) 

and  f .  typica  of  strain  C,  f .  typica  of  strain  E,  and  mut.  formosa 8 

Various  pedigrees  of  plants  used  in  crosses 9 

DISCUSSION 10 

SUMMARY 13 

LITERATURE  CITED 15 

APPENDIX — TABLES 15 

INTRODUCTION 

In  the  study  of  heredity  in  the  genus  Oenothera  simple  Mendelian  results 
are  very  rarely  obtained.  It  is  generally  conceded  that  the  unusual  results 
are  due  to  the  production,  by  a  single  morphologically  uniform  strain,  of 
gametes  of  more  than  one  type.  The  explanations  have  been  various. 
The  mutation  hypothesis  of  DE  VRIES  is  of  course  well  known.  It  has  not 
been  generally  accepted,  however,  as  originally  proposed.  MORGAN  (1918) 
and  MULLER  (1918)  have  suggested  point  mutation,  followed  by  crossing 
over,  an  explanation  suggested  by  their  work  on  Drosophila.  MULLER 
has  worked  out  experimentally  a  balanced  lethal  stock  of  Drosophila  in 
which  certain  seemingly  aberrant  phenomena  of  the  Oenotheras  find  a 
parallel.  To  what  extent  the  parallel  affords  an  explanation  we  can  not 
judge  until  the  genetic  analysis  of  the  Oenotheras  has  been  carried  further. 

1  Papers  from  the  Department  of  Botany  of  the  UNIVERSITY  OF  MICHIGAN,  No.  181. 
GFNETICS  6:1    Ja  1921 

458726 


2  FRIEDA  COBB 

The  present  paper  is  a  contribution  to  the  genetic  analysis  of  Oenothera 
pratincola.  It  deals  exhaustively  with  the  first  case  in  which  simple 
Mendelian  inheritance  has  been  recognized  and  conclusively  demonstrated 
when  complicated  by  phenomena  peculiar  to  the  Oenotheras. 

The  strains  of  Oenothera  pratincola  used  in  this  investigation  were  those  of 
which  the  history  has  already  been  published  (BARTLETT  1915  a,  b;  COBB 
and  BARTLETT  1919).  Although  morphologically  alike,  one  of  them,  desig- 
nated as  strain  E,  is  genetically  different  from  the  other  seven,  of  which 
strain  C,  the  strain  used  in  the  experiments  recorded  in  this  paper,  is  a 
typical  example. 

Strain  C  produces  in  every  generation  a  small  number  of  mutations  of 
several  kinds  (BARTLETT  1915  a).  Some  of  these  kinds  appear  also  in 
strain  E,  but  much  more  conspicuous  in  strain  E  are  numerous  mutations, 
of  a  strikingly  distinct  series,  which  do  not  occur  in  the  other  strains. 
These  mutations  occur  in  such  numbers  as  to  merit  the  term  mass  muta- 
tion (BARTLETT  1915  b)  as  a  designation  of  the  phenomenon.  The  series 
consists  of  four  distinct  types,  all  alike  in  having  narrow,  strongly  revolute 
leaves,  and  in  producing  nothing  butrevolute-leaved  plants  in  their  progenies. 
Of  these  revolute-leaved  mutations,  mut.  formosa  (BARTLETT  1915  b),  the 
strongest  and  most  fertile  of  the  series,  was  crossed  with  f .  typica  of  strain 
E,  and  with  strain  C. 

In  a  former  paper  (COBB  and  BARTLETT  1919)  it  has  been  stated  that  in 
reciprocal  crosses  between  mut.  formosa  and  f .  typica  E,  from  which  mut. 
formosa  arises,  inheritance  is  matroclinic.  Strain  C  pollinated  by  mut. 
formosa  gives  a  matroclinic  progeny;  but  the  reciprocal  cross,  mut.  formosa 
pollinated  by  strain  C,  gives  in  the  FI  generation  only  f.  typica,  in  the  F2 
generation  a  Mendelian  segregation  of  3  f.  typica:  1  mut.  formosa. 

HYPOTHESIS  OF  HETEROGAMETISM 

The  hypothesis  of  heterogametism  offered  (COBB  and  BARTLETT  1919) 
in  explanation  of  these  phenomena,  assumes  that  two  types  of  gametes 
occur  in  Oenothera  pratincola,  a  gametes  (usually  female)  and  0  gametes 
(usually  male),  the  a  gametes  carrying  some  factors  not  represented  in  the 
0  gametes.  Each  zygote  is  formed  by  the  union  of  an  a  and  a  /3  gamete, 
and  so  gets  (except  in  rare  cases  of  metacliny)  the  a  determiners  of  its 
pistillate  parent  and  the  0  determiners  of  its  staminate  parent.  It,  in 
turn,  produces  a  (female)  and  0  (male)  gametes.  In  the  case  of  a  cross, 
the  zygote  is  quite  unaffected  by  the  nature  of  the  a  of  its  staminate  parent 
and  the  /3  of  its  pistillate  parent. 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA  3 

Besides  its  characteristic  a  or  ft  part,  each  gamete  carries  a  group  of 
factors  common  to  both  a  and  ft  gametes.  The  characteristic  a  and  ft 
portions  of  the  gametes  may  consist  of  a  single  chromosome  or  of  a  group 
of  chromosomes,  but  probably  the  latter,  for  very  few  characters  have 
been  found  which  are  not  connected  with  the  a  or  ft  portions  of  the  gametes. 
At  reduction,  a  and  ft  behave  as  units;  that  is,  there  is  no  interchange  of 
factors  or  chromosomes  between  the  characteristic  a  and  ft  portions,  each 
passing  into  the  gametes  (the  a  into  the  female,  the  ft  into  the  male)  just 
as  it  entered  the  zygote  from  the  parent.  There  is,  however,  the  usual 
free  segregation  among  the  remainder  of  the  chromosomes,  each  member  of 
the  homologous  pairs  accompanying  with  equal  frequency  the  a  and  the  ft 
portions.  Thus  factors  entering  a  zygote  in  the  characteristic  a  or  ft 
chromosome  (or  chromosomes)  occur  in  the  a  or  ft  gametes,  respectively, 
which  it  produces ;  but  those  factors  which  entered  the  zygote  in  the  remain- 
ing, freely  segregating  group  of  chromosomes,  occur  as  frequently  in  the 
a  as  in  the  ft  gametes  produced.  Characters  whose  factors  belong  to  the 
a  or  to  the  ft  portion  are  inherited  matroclinically  or  patroclinically,  respec- 
tively; those  whose  factors  belong  to  homologous  and  freely  segregating 
chromosomes  common  to  both  a  and  ft  gametes  are  inherited  in  a  Men- 
delian  manner. 

Mut.  formosa  arose  from  i.  typical  by  modification  of  a  factor  for  flatness 
in  the  a  portion  of  the  a  gamete,  that  is,  by  change  of  a  factor  which  has  no 
counterpart  in  the  ft  portion  of  the  ft  gamete.  Change  being  in  the  a 
(female)  gamete  only,  inheritance  in  crosses  between  mut.  formosa  and  f . 
typica  E  is,  therefore  matroclinic.  If  mut.  formosa  is  used  as  the  pistillate 
parent  the  a  gamete  received  by  the  progeny  is  the  mutated  a  of  mut. 
formosa  (designated  hereafter  as  <*'),  and  the  progeny  is  therefore  mut. 
formosa;  if  f.  typica  is  used  as  the  pistillate  parent  the  a  gamete  received 
by  the  progeny  is  the  normal  a  gamete  of  Oenothera  pratincola,  and  the 
progeny  is  f .  typica. 

Strain  C  differs  from  strain  E  in  having,  in  addition  to  the  factor  for 
flatness  in  the  a  portion  of  the  a  gamete,  a  freely  segregating  (Mendelian) 
factor  for  flatness  (F)  present  in  both  a  and  ft  gametes,  of  which  the  reces- 
sive allelomorph  (/)  is  carried  by  strain  E.  Thus  the  constitution  of 
strain  C  is  aftFF,  and  the  gametes  which  it  produces  are  aF  (female)  and 
ftF  (male).  The  constitution  of  strain  E  is  aftff,  and  the  gametes  which 
it  produces  are  af  (female)  and  ftf  (male).  The  constitution  of  mut. 
formosa  is  a'ftff,  and  the  gametes  which  it  produces  are  a'f  (female)  and 
ftf  (male).  Therefore  strain  C  (aftFF)  pollinated  by  mut.  formosa  (a'ftff) 
gives  a  flat-leaved  progeny  (a&Ff)  which  breeds  true,  for  the  a  gamete 

GENETICS  6  :    Ja  1921 


4  FRIEDA  COBB 

concerned  in  the  cross  is  normal;  but  mut.  formosa  (aftff)  pollinated  by 
strain  C  (afiFF)  gives  a  flat-leaved  progeny  (a'pFf)  (flat-leaved,  notwith- 
standing the  mutated  condition  of  a,  because  of  the  presence  of  one  Men- 
delian factor  for  flatness,  inherited  from  the  pistillate  parent)  which  shows 
in  the  next  generation  a  Mendelian  segregation  of  flat-leaved  plants  (a$FF 
and  a.'&Ff)  and  revolute-leaved  plants  (a$ff).  Thee/  gamete  concerned 
in  the  cross  has  lost  the  factor  for  flatness,  and  so  those  F2  individuals 
that  are  recessive  for  the  Mendelian  factors  for  flatness  show  the  revolute- 
ness  determined  by  a '.  This  new  synthetic  f.  typica  (a&FF  or  afiFf), 
differing  in  genetic  composition  from  both  f .  typica  C  and  f.  typica  E,  carry- 
ing the  factor  for  revoluteness  masked  by  at  least  one  of  the  Mendelian 
pair  of  factors  for  flatness,  will  be  called  f.  typica  M  (homozygous  or  hete- 
rozygous, as  the  case  may  be). 

The  hypothesis  of  the  genetic  constitution  of  the  plants,  and  the  results 
of  crossing,  may  be  stated  in  brief  as  follows: 

Strain  C,  apFF,  flat,  and,  with  respect  to  this  char- 

acter, immutable. 

Strain  E,  aftff,   flat,  mutable. 

Mut.  formosa,  a'Pff,  revolute-leaved. 

Strain  E  X  formosa,  aflff,   flat,  mutable. 

Formosa  X  strain  E,  a'pff  revolute,  breeding  true  with  respect  to 

this  character. 

Strain  C  X  formosa,  a(3Ff  flat,  segregating  with  respect  to  muta- 

bility. 

1  a0FF  flat,  immutable,  breeding  true. 

2  a0Ff  flat,  continuing  the  segregation  of  the 

Fi  generation. 

1  apff  flat,  mutable,  otherwise  breeding  true. 
Formosa  X  strain  C,          a'&Ff  flat,  segregating  with  respect  to  revo- 
luteness. 
1  a&FF  flat,  non-segregating. 

(Formosa  X  strain  C)  FJ2  «'W^<  continuing  the  segregation  of  the 

FI  generation. 
1  o'jSjfjT  revolute,  breeding  true. 

EQUIVALENCE,   WITHIN  STRAIN  C,   OF  POLLEN  OF   OENOTHERA  PRATINCOLA 
F.   TYPICA  AND  MUT.   LATIFOLIA 

The  former  paper  (COBB  and  BARTLETT  1919)  gave  data  of  the  F,  and 
F2  generations  of  the  cross  mut.  formosa  E  X  mut.  latifolia  C.  At  the 
time  the  original  crosses  between  mut.  formosa  and  strain  C  were  made, 


(Strain  C  X  formosa)  F2 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA  5 

the  cross  mut.  formosa  X  f .  typica  C  was  unsuccessful.  But  the  pollen  of 
mut.  latifolia  had  been  shown  to  be  equivalent  to  the  pollen  of  the  f .  typica 
from  which  it  arises  (the  mutation  to  latifolia  being  concerned  with  the 
a  gamete,  the  /?  gamete  remaining  as  in  f.  typica),  and  therefore,  in  order 
to  have  a  more  complete  series  of  crosses  to  work  upon,  the  cross  mut. 
formosa  X  mut.  latifolia  from  strain  C  was  used  in  place  of  the  missing 
cross,  mut.  formosa  X  f .  typica  C.  The  substitution  has  been  justified  by 
later  work,  recorded  in  tables  5  and  6  of  the  present  paper,  which  give  anal- 
yses of  the  Fi  and  F2  generations  of  the  cross  mut.  formosa  X  f .  typica  C. 
This  cross  was  successfully  made  three  years  after  the  original  crosses 
upon  which  much  of  the  work  recorded  here  is  based. 

The  Fi  generation  (see  table  5)  consisted  of  100  plants  from  six  different 
crosses,  all  of  them  flat-leaved.  The  F2  generation  (see  table  6)  consisted 
of  3274  plants,  2399  flat-leaved  and  875  revolute-leaved;  that  is,  a  ratio  of 
2.74:1,  in  sufficiently  good  accord  with  the  3:1  of  the  Mendelian  mono- 
hybrid  ratio.  The  cross  mut.  formosa  X  mut.  latifolia  C,  as  recorded  in 
the  previous  paper,  gave  in  the  FI  generation  209  plants,  all  of  them  flat- 
leaved,  and  in  the  F2  generation  from  normal  f.  typica  plants  of  the  FI 
generation,  6392  plants,  4759  flat-leaved  and  1633  revolute-leaved;  that  is, 
a  ratio  of  2.91 : 1.  This  shows  that  the  results  in  the  F2  generation  are  the 
same  whether  mut.  formosa  is  pollinated  by  f .  typica  C  or  by  mut.  latifolia 
C ;  and  this,  in  connection  with  the  previous  evidence  (CoBB  and  B ARTLETT 
1919)  of  the  equivalence  of  the  pollen  from  the  two  sources,  gives  ample 
justification  for  the  substitution  of  f.  typica  M  descended  from  mut.  lati- 
folia instead  of  the  identical  form  descended  from  f.  typica  C. 

THE  F3  AND  F4  GENERATIONS  OF  THE  CROSS  MUT.  FORMOSA  FROM  STRAIN  E 
X  MUT.  LATIFOLIA  FROM  STRAIN  C 

The  F3  and  F4  generations  of  the  cross  mut.  formosa  X  mut.  latifolia  C 
show  a  continuance  of  the  Mendelian  behavior  of  the  F2  generation  (COBB 
and  BARTLETT  1919).  Self-pollination  of  normal  f.  typica  plants  of  the  F2 
generation  gave  in  the  F3  generation  (see  table  2)  22  progenies  consisting 
entirely  of  flat-leaved  plants,  showing  the  presence  of  homozygous  dom- 
inants (a'(3FF)  in  the  F2  generation,  and  41  progenies  in  which  there  were 
both  flat-leaved  and  revolute-leaved  plants,  showing  the  presence  of 
heterozygous  dominants  (a'pFf)  in  the  F2  generation.  The  ratio  22  uni- 
form cultures  to  41  segregating  cultures  very  closely  approximates  the 
expected  ratio  of  1  homozygous  dominant  to  2  heterozygous  dominants 
in  the  F2  generation.  In  the  segregating  progenies  of  the  F3  generation 

GENETICS  6  :    Ja  1921 


6  FRIEDA  COBB 

the  ratio  of  flat-leaved  to  revolute-leaved  plants  is  3.08:1,  in  very  close 
agreement  with  the  expected  3 : 1  of  the  Mendelian  monohybrid  segregation. 

All  progenies  of  fewer  than  20  plants  were  omitted  from  table  2  as  being 
unreliable.  A  very  small  culture  of  flat-leaved  plants  might,  had  it  been 
larger,  have  included  some  revolute-leaved  plants,  and  thus  a  heterozygous 
dominant  of  the  F2  generation  might  be  recorded  as  homozygous.  If  these 
cultures  were  included  in  the  table,  the  ratio  of  non-segregating  to  segre- 
gating progenies  would  become  33:56  instead  of  22:41,  and  the  ratio  of 
flat-leaved  to  revolute-leaved  plants  in  the  segregating  progenies  would 
become  2.94: 1  instead  of  3.08: 1. 

Self-pollination  of  16  plants  of  f .  typica  M  (a'&FF)  belonging  to  the  non- 
segregating  cultures  of  the  F3  generation  gave  in  the  F4  generation  (see 
table  3)  1114  plants,  all  of  them  flat-leaved.  From  these  plants  an  F5 
generation  has  been  grown,  consisting  of  695  plants  belonging  to  7  prog- 
enies, no  progeny  consisting  of  fewer  than  29  plants.  All  were  flat-leaved. 
Self-pollination  of  3  plants  chosen  at  random  among  the  f .  typica  plants  of 
the  segregating  cultures  of  the  F3  generation  gave  in  the  F4  generation  (see 
table  4)  2  segregating  progenies  and  1  non-segregating,  showing  a  continu- 
ance of  the  Mendelian  splitting  to  the  fourth  filial  generation.  It  seems 
unnecessary  to  carry  the  line  further. 

The  behavior  of  the  recessives,  mut.formosa  (a'Pff),  of  the  F2  generation 
of  the  cross  mut.formosa  X  mut.  latifolia  C.  was  also  in  accord  with  expec- 
tation. The  F3  generation  consisted  of  69  plants  belonging  to  progenies 
of  4  mut.  formosa  plants  of  the  F2  generation.  All  were  revolute-leaved, 
and  the  62  grown  to  maturity  all  proved  to  be  mut.  formosa.  Also,  2388 
plants  belonging  to  the  F3  progenies  from  mut.  formosa  plants  of  the  F2 
generation,  of  the.  cross  mut.formosa  X  CD  hyb.  viscida  were  all  revolute- 
leaved.  Hyb.  viscida  is  the  form  resulting  from  the  cross  Oenothera  pratin- 
cola  f.  typica  C  X  Oenothera  numismatica  (BARTLETT  1915  a).  It  is  like 
f.  typica  C  in  all  respects,  except  that,  in  addition  to  the  pubescence  nor- 
mally occurring  on  the  flowers  of  Oenothera  pratincola,  it  has  the  viscid 
pubescence  of  Oenothera  numismatica. 

THE  FI  AND  F2  GENERATIONS   OF  THE  CROSS  F.  TYPICA,   STRAIN  C    X    MUT. 

FORMOSA,  STRAIN  E 

j 

The  Mendelian  behavior  following  the  cross  mut.  formosa  X  strain  C 
has  been  demonstrated  at  length.  The  reciprocal  cross,  f.  typica  C  X 
mut.  formosa  (afiFF  X  a'pff),  is  just  as  Mendelian  in  its  segregation  of  the 
free  factors  for  flatness,  but  the  Mendelian  segregation  of  factors  finds  no 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA  7 

chance  to  express  itself  in  the  zygote  because  of  the  ever-present  a  factor 
for  flatness  inherited  from  the  pistillate  parent.  The  only  way  for  a  revo- 
lute-leaved  plant  to  occur  in  the  F2  or  following  generations  of  the  cross  is 
by  an  independent  mutation  from  a  to  a  in  the  presence  of  the  recessive 
condition  of  the  Mendelian  factors  for  flatness.  Only  one-fourth  of  the 
plants  of  the  F2  generation,  those  with  the  constitution  apff,  are  capable 
of  becoming  revolute-leaved  by  mutation.  Apparently  there  is  nothing 
to  hinder  mutation  from  a  to  a  in  strain  C.  But  in  pure  strain  C  the 
change  would  not  be  indicated  by  outward  sign,  for  the  strain  is  homo- 
zygous  for  the  Mendelian  factors  for  flatness.  That  this  change  does 
sometimes  occur  is  shown  by  the  few  revolute-leaved  plants  which  occur 
in  the  F2  generation  of  the  cross  f .  typica  C  X  mut.  formosa  (see  table  8, 
and  COBB  and  BARTLETT  1919,  table  6).  In  table  8  there  are  26  revolute- 
leaved  plants  in  a  total  of  1654,  or  16  per  1000.  If  the  mutation  to  a' 
should  take  place  in  a  plant  of  the  FI  generation  (a&Ff),  a  3: 1  ratio  would 
occur  in  the  F2  generation.  In  the  hope  that  this  may  sometime  happen 
in  the  experiment  garden,  the  cross  f.  typica  C  X  mut.  formosa  has  been 
repeated  many  times,  and  FI  and  F2  progenies  are  being  grown. 

THE  FI  AND  F2  GENERATIONS  OF  THE  CROSS  MUT.  FORMOSA  STRAIN  E    X    F. 

TYPICA    STRAIN    E 

In  the  cross  mut.  formosa  X  f .  typica  E  (afiff  X  aQff)  the  mechanism 
for  Mendelian  inheritance  operates  just  as  certainly  as  in  the  correspond- 
ing cross  with  f.  typica  C,  but  the  two  parents  happen  to  be  alike  in  the 
Mendelian  factors  under  consideration,  both  being  pure  recessives,  so  the 
only  type  of  inheritance  which  manifests  itself  is  matrocliny,  depending  on 
the  difference  in  factorial  composition  of  the  characteristic  portions  of  the 
a  and  )8  gametes.  This  cross  has  been  repeated  successfully  nine  times, 
giving  305  plants  in  the  FI  generation  (see  table  9)  and  628  plants,  from 
four  plants  of  the  FI  generation,  in  the  F2  generation  (see  table  10).  All 
of  the  plants  of  both  generations  were  revolute-leaved.  The  inheritance 
here  is  matroclinic,  in  contrast  with  the  Mendelian  inheritance  in  the  cor- 
responding cross  with  strain  C. 

The  reciprocal  cross,  f.  typica  E  X  mut.  formosa  (afiff  X  otfiff),  has  not 
been  successfully  repeated  since  the  publication  (COBB  and  BARTLETT 
1919)  of  the  fact  that  this  cross  is  also  matroclinic,  the  number  of  revolute- 
leaved  plants  occurring  in  the  progeny  being  no  greater  than  might  be 
expected  from  self-pollination  of  f.  typica  plants  of  strain  E,  the  strain 
which  regularly  produces  some  revolute-leaved  plants  in  every  generation. 

GENETICS  6  :    Ja  1921 


8  FRIEDA  COBB 

THE   FI   AND   F2   GENERATIONS   OF   VARIOUS   CROSSES   BETWEEN   F.   TYPICA   M 

(THE  NEW,  MENDELIAN  STRAIN)  AND  F.  TYPICA  OF  STRAIN  c, 

F.   TYPICA  OF   STRAIN  E,  AND  MUT.   FORMOSA 

The  data  recorded  in  this  paper  concerning  the  FI  and  F2  generations 
of  crosses  of  eighteen  different  kinds  between  f .  typica  M  (the  new  Men- 
delian  strain  from  the  cross  mut.  formosa  X  strain  C)  as  one  parent,  and 
f.  typica  C,  f.  typica  E,  or  mut.  formosa,  as  the  other  parent,  confirm  the 
hypotheses  of  non-equivalent  gametes  and  the  presence  of  a  pair  of  inde- 
pendent Mendelian  factors  in  Oenothera  pratincola. 

All  f.  typica  M  plants  used  in  the  crosses  were  self -pollinated  to  deter- 
mine whether  they  were  homozygous  or  heterozygous. 

All  of  the  flat-leaved  types  other  than  f.  typica  which  occurred  in  the 
progenies  of  crosses  are  mutations  regularly  thrown  by  f.  typica  C,  and 
some  of  them  by  f.  typica  E  also.  All  of  the  revolute-leaved  types  which 
occurred,  are  regularly  thrown  by  f .  typica  E  and  by  mut.  formosa. 

The  cross  mut.  formosa  X  f .  typica  M  (homozygous)  (afrff  X  a$FF) 
gave  in  the  Fi  generation  (see  table  11)  only  flat-leaved  plants  (a'(3Ff), 
and  in  the  F2  generation  (see  table  12)  a  segregation  of  3  flat-leaved  plants 
(a'QFF  and  a'QFf)  to  1  revolute-leaved  plant  (a'fff). 

The  reciprocal  cross,  f .  typica  M  (homozygous)  X  mut.  formosa  (a' 
X  afiff),  gave  the  same  results  (see  tables  13  and  14). 

The  cross  mut.  formosa  X  f .  typica  M  (heterozygous)  (aftff  X  a 
gave  in  the  Fi  generation  (see  table  15)  progenies  consisting  of  flat-leaved 
plants  (a&Ff)  and  revolute-leaved  plants  (aftff)  in  approximately  equal 
numbers,  and  in  the  F2  generation  from  flat-leaved  plants  (see  table  16)  a 
segregation  of  3  flat-leaved  plants  (a'pFF  and  a'flFf)  to  1  revolute-leaved 
plant  (a'fff). 

The  reciprocal  cross,  f.  typica  M  (heterozygous)  X  mut.  formosa  (a'ftFJ 
X  arpff)  gave  the  same  results  (see  tables  17  and  18). 

The  cross  f .  typica  E  X  f .  typica  M  (homozygous)  (a/3//  X  a'QFF)  gave 
in  both  the  Fi  and  the  F2  generations  (see  tables  19  and  20)  only  flat-leaved 
plants.  It  is  known  that  the  a  of  strain  E  frequently  mutates  to  a',  and  a 
few  revolute-leaved  plants  would  therefore  be  expected  in  the  F2  progenies, 
by  a  combination  of  a  and  the  recessive  Mendelian  factors.  One-fourth 
of  the  plants  of  the  F2  generation,  those  with  the  constitution  aftff,  would 
be  expected  to  become  revolute-leaved  by  mutation  with  the  frequency 
of  mutation  in  pure  strain  E.  But  this  did  not  occur.  The  only  explana- 
tion that  can  be  suggested  is  that  because  the  germination  percentage  was 
much  higher  than  was  expected,  the  seedlings  were  very  much  crowded  in 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA  9 

the  seed-pans,  and  possibly  revolute-leaved  plants,  which  do  not  hold  their 
own  in  a  dense  stand,  died  before  the  seedlings  were  counted  off.  This, 
however,  does  not  seem  likely,  and  the  matter  will  be  further  investigated. 

The  reciprocal  cross,  f .  typica  M  (homozygous)  X  f.  typica  E  (a'fiFF  X 
aftff),  gave  in  the  FI  generation  (see  table  21)  only  flat-leaved  plants 
(a'fiFf)  and  in  the  F2  generation  (see  table  22)  a  segregation  of  3  flat-leaved 
plants  (a'fiFF  and  cf&Ff)  to  1  revolute-leaved  plant  (aftffl. 

The  cross  f .  typica  M  (heterozygous)  X  f .  typica  E  (a'fiFf  X  a$f)  gave 
in  the  FI  generation  (see  table  23)  flat-leaved  plants  (a0Ff)  and  revolute- 
leaved  plants  (a'pff)  in  about  equal  numbers,  and  in  the  F2  generation 
from  flat-leaved  plants  (see  table  24)  a  segregation  of  3  flat-leaved  plants 
(a'pFF  and  a'pFf)  to  1  revolute-leaved  plant  (a'fff). 

The  reciprocal  cross  is  missing  from  the  series. 

The  cross  f.  typica  M  (homozygous)  X  f.  typica  C  (a'&FF  X  a@FF) 
gave  in  both  the  FI  and  F2  generations  (see  tables  25  and  26)  only  flat- 
leaved  plants  (a'pFF  in  both  generations) . 

The  reciprocal  cross  is  missing  from  the  series. 

The  cross  f.  typica  M  (heterozygous)  X  f.  typica  C  (a'QFf  X  aQFF) 
gave  in  the  FI  generation  (see  table  27)  only  flat-leaved  plants  (afiFF 
and  a'pFf)  and  in  the  F2  generation  (see  table  28)  11  progenies  consisting 
entirely  of  flat-leaved  plants  (a'pFF)  and  7  progenies  showing  a  segrega- 
tion of  3  flat-leaved  plants  (a'pFF  and  a'pFf)  to  1  revolute-leaved  plant 
(a* ftff) .  The  ratio  11:7  does  not  approach  as  closely  as  would  be  expected 
the  ratio  of  one  dominant  factor  to  one  recessive  factor  in  the  gametes  of 
the  heterozygous  pistillate  parent  of  the  cross.  In  this  table  there  seems 
to  be  a  shortage  both  of  segregating  progenies  and  of  revolute-leaved  plants 
in  the  segregating  progenies,  indicating  that  the  pistillate  parent  and  its 
progeny  produce  either  fewer  or  weaker  gametes  bearing  the  recessive 
factor. 

The  reciprocal  cross  is  missing  from  the  series. 

A  summary  of  tables  5  to  28,  inclusive,  is  given  as  table  29. 

VARIOUS  PEDIGREES  OF  PLANTS  USED  IN  CROSSES 

A  record  of  the  parentage  of  all  of  the  plants  used  in  this  work  is  given 
as  table  1.  All  plants  not  otherwise  designated  were  f.  typica. 

It  may  be  noticed  that,  though  different  strains  of  Oenothera  pratincola 
behave  differently  as  to  the  mutations  that  they  throw  when  self -pollinated, 
and  in  the  way  that  they  behave  in  crosses,  all  f.  typica  plants  within  a 
strain,  no  matter  how  complicated,  by  crossing  or  mutation,  their  pedi- 

GENETICS  6  :    Ja  1921 


10  FRIEDA  COBB 

grees  may  be,  act  in  the  same  way.  For  instance,  an  f.  typica  from  mut. 
grisella  from  f.  typica  C  behaves  exactly  as  f.  typica  C  with  no  mutations 
in  its  direct  ancestry,  at  least  during  the  period  in  which  the  strain  has 
been  carried  in  the  garden. 

It  may  also  be  noted  that  all  plants  of  mut.  formosa  appear  the  same 
and  behave  the  same  genetically  regardless  of  extraction.  Those  used  in 
crosses  were  of  five  different  types  of  extraction:  (1)  directly  from  f.  typica 
E,  by  self-pollination;  (2)  from  f.  typica  E,  first  by  mutation  to  angusti- 
folia,  then  to  mut.  nitidissima  and  finally  to  mut.  formosa,  all  by  self- 
pollination;  (3)  from  the  cross  mut.  formosa  X  f.  typica  E,  by  matroclinic 
inheritance;  (4)  from  the  cross  mut.  formosa  X  strain  C,  by  segregation; 
(5)  from  crosses  with  both  strain  C  and  strain  E,  by  segregation  and  matro- 
clinic inheritance,  e.g.,  (  (mut.  formosa  X  mut.  latifolia  C}— mut.  formosa 
X  f .  typica  E) — mut.  formosa. 

In  many  thousand  offspring,  mut.  formosa  has  produced  nothing  but 
revolute-leaved  plants. 

DISCUSSION 

It  may  seem  to  those  who  are  used  to  working  with  organisms  in  which 
clear  Mendelian  inheritance  is  the  usual  thing,  that  this  case  in  Oenothera 
pratincola  has  been  worked  out  with  unnecessary  elaboration.  But  several 
considerations  should  be  borne  in  mind:  first,  that  evident  Mendelian 
inheritance  is  so  rare  in  Oenothera  that  only  two  indisputable  cases  have 
been  recorded,  that  of  mut.  brevistylis  (DE  VRIES  1901,  p.  223;  1903,  pp. 
151-179,  429)  and  that  of  the  dwarf  mutation  from  mut.  gigas  (DE  VRIES 
1915 b)  and  that  all  instances  deserve  therefore  to  be  thoroughly  examined; 
second,  that  in  this  case  the  Mendelian  inheritance  is  apparently  modified 
by  inheritance  of  another  kind,  working  simultaneously  with  and  inde- 
pendently of  the  Mendelian  inheritance;  and  third,  that  the  hypothesis  of 
heterogametism  put  forth  to  explain  this  other  type  of  inheritance  needs 
further  testing. 

If  the  explanations  offered  here  are  correct,  we  have,  in  addition  to 
Mendelian  inheritance  masked  by  heterogametism,  mutation  masked  by 
Mendelian  factors.  That  the  a  of  strain  C  can  undergo  mutation  to  a.'  is 
shown  by  the  presence  of  a  few  revolute-leaved  plants  in  the  F2  generation 
of  the  cross  f .  typica  C  X  mut.  formosa.  These  plants  derive  their  a  from 
strain  C,  but  have  the  dominant  Mendelian  factors  which  are  present  in 
strain  C  replaced  by  their  recessive  allelomorphs  (see  table  8).  There 
seems  no  reason  to  doubt  that  this  mutation  in  a  occurs  just  as  frequently 
in  the  presence  of  the  Mendelian  factors  for  flatness  (i.e.,  in  pure  strain  C) 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA  11 

as  in  their  absence.  If  such  is  the  case,  Mendelian  factors  hide  the  muta- 
tion until  a  suitable  cross  occurs  to  remove  the  factors.  This  may  have 
some  bearing  on  the  question  whether  crossing  induces  mutation;  it  may 
be  that  crossing  merely  makes  possible  an  external  expression,  by  removing 
concealing  Mendelian  factors,  of  changes  which  occurred  long  since  in  the 
germ-plasm  and  have  been  passed  on  from  generation  to  generation  giving 
no  visible  sign  of  their  presence.  In  the  same  way  a  single  mutation,  the 
loss  of  one  concealing  factor,  in  a  single  chromosome,  might  bring  to  light 
a  whole  series  of  new  forms.  (The  several  revolute-leaved  types  that  have 
occurred  in  the  experiment  garden  can  all  be  permanently  concealed  by  the 
single  pair  of  Mendelian  factors  for  flatness.)  This  may  explain  in  part 
the  apparent  periodicity  of  mutability.  Perhaps  the  organism  does  not 
have  increased  tendency  to  change,  but  hoards  actual  changes  until  chance 
brings  them  to  light,  "gruppenweise,"  by  the  removal  of  inhibiting  factors 
through  a  mutation. 

Though  the  condition  of  the  Mendelian  factors  in  Oenothera  pratincola 
strains  other  than  strains  C  and  E  has  not  been  investigated,  it  seems 
probable,  since  they  have  given  no  revolute-leaved  plants,  that  the  other 
six  strains  are  homozygous  with  regard  to  the  factor  for  flatness.  If  strain 
E  is  the  only  one  of  the  eight  strains  carrying  the  recessive  factors,  it  might 
seem  likely  that  it  arose  from  one  of  the  other  strains  by  loss  of  a  dominant 
factor,  and  consequent  Mendelian  segregation,  rather  than  that  the  reverse 
change  took  place,  were  it  not  for  the  fact  that  strain  E  has  produced  in 
the  experiment  garden  a  mutation  (mut.  nitidissima)  which,  as  shown  by 
its  behavior  in  crosses  with  mut.  formosa,  is  a  homozygous  dominant  in 
regard  to  the  Mendelian  factors  for  flatness.  Whether  both  dominant 
factors  were  present  in  the  original  plant  of  mut.  nitidissima  and  its  FI 
generation  is  a  question  which  cannot  be  answered,  but  it  is  clear  that  they 
are  now  present  in  the  strain  as  it  is  carried  on  in  the  garden. 

That  a  pure  dominant  strain  might  arise  from  a  pure  recessive  strain, 
or  the  reverse,  leaving  no  heterozygous  plants  to  tell  the  tale,  seems  pos- 
sible, for  the  heterozygotes,  as  they  appear  in  the  experiment  garden,  tend 
to  have  poor  and  irregular  leaf  development  as  young  rosettes,  and  might 
easily  be  eliminated  by  natural  selection.  The  modification  of  a  factor 
for  flatness  in  a  single  chromosome  of  a  homozygous  dominant,  or  the 
reverse  modification  in  a  homozygous  recessive,  would  then  be  the  only 
change  in  the  germ-plasm  necessary  to  produce  one  homozygous  strain 
from  the  other. 

Some  explanation  should  be  made  of  the  unusually  low  germination  per- 
centages occurring  in  the  cultures  recorded  in  this  investigation.  As  the 

GENETICS  6:    Ja  1921 


12  FRIEDA  COBB 

character  flatness  vs.  revoluteness  is  one  which  is  evident  in  even  very 
young  seedlings,  many  sowings  were  made  merely  for  the  sake  of  recording 
the  nature  of  the  seedlings,  and  the  seedlings  were  then  discarded.  In 
order  to  give  all  possible  space  and  attention  to  the  cultures  intended  for 
the  summer  garden  at  the  time  which  is  most  favorable  for  planting,  the 
sowings  for  seedling  counts  were  made  early  and  got  out  of  the  way.  This 
meant  that  the  seeds  did  not  have  as  long  a  rest  period  as  they  apparently 
need  before  germination.  Had  they  been  planted  a  month  or  two  later 
(in  February  and  March  instead  of  December  and  January)  the  percent- 
ages of  germination  would  have  been  very  much  higher. 

In  problems  connected  with  comparative  fertility  and  sterility  it  is 
of  course  quite  necessary  to  know  that  all  viable  seeds  are  forced  to  ger- 
minate. The  method  worked  out  by  DE  VRIES  (1915  a)  and  applied  by 
DAVIS  (1915)  for  forcing  germination  to  completion,  is  especially  suited 
to  such  problems.  It  will  also  throw  light  on  the  types  that  may  be  lost 
through  selective  mortality  and  selective  germination  rate  when  less 
thorough  methods  are  used.  This  information  is  most  valuable.  But 
that  the  low  germination  percentage  has  no  significant  effect  on  the  results 
of  the  experiments  recorded  here  is  shown  by  table  30.  Here  the  ratios 
of  flat-leaved  to  revolute-leaved  plants  are  assembled  from  all  of  those 
cultures  in  which  the  expected  ratio  is  3:1,  and  arranged  according  to  the 
germination  percentage.  It  will  be  seen  that  three-fourths  of  the  cultures 
have  a  germination  percentage  under  25  percent.  But  it  may  also  be 
seen  that  the  average  of  the  ratios  of  cultures  in  which  the  germination  is 
from  50  to  81  percent  is  no  nearer  the  expected  3:1  ratio  than  are  the 
averages  from  cultures  with  poorer  germination.  Even  when  less  than  5 
percent  of  the  seeds  germinated,  the  average  is  as  close  to  the  theoretical 
ratio  as  is  that  of  any  one  of  the  five  cultures  with  a  germination  over  50 
percent,  or  as  the  average  of  these  five  cultures. 

That  selective  germination,  in  connection  with  the  types  with  which  this 
problem  is  concerned,  occurs  to  any  significant  extent  seems  impossible. 
The  only  evidence  of  such  selection  is  a  slight  excess  of  revolute-leaved 
individuals,  especially  noticeable  when  the  germination  is  poorer.  There 
are  four  tables  which  show  in  the  total  an  excess  of  flat-leaved  plants,  ten 
which  show  an  excess  of  revolute-leaved  plants.  In  work  with  this  species 
it  has  been  noticed  that  when  the  percentage  of  germination  is  very  low 
the  percentage  of  mutations  is  very  high  (BARTLETT  1915  a).  General 
observations  lead  to  the  conclusion  that  poor  germination  tends  to  bring 
the  unusual  types  into  prominence  rather  than  to  conceal  them. 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA  13 

This  paper  records  the  case  of  a  single  unit  character  of  the  zygote, 
revoluteness,  determined  by  a  complicated  set  of  phenomena:  an  allelo- 
morphic  pair  of  factors  (F  and  /),  the  dominance  and  recessiveness  of 
which  produce  no  effect  on  the  zygote  except  when  the  particular  muta- 
tional  change  from  a  to  a  has  taken  place;  a  mutation  (a  to  a)  occurring 
repeatedly,  but  concealed,  as  long  as  self-pollination  continues,  by  the 
Mendelian  factors  FF,  and  Mendelian  segregation  concealed  by  matro- 
clinic  inheritance  dependent  on  heterogametism  (a  and  /3  gametes).  It  is 
hoped  that  the  case  may  help  to  throw  light  upon  the  seemingly  peculiar 
behavior  of  the  Oenotheras. 

SUMMARY 

1.  The  male  and  female  gametes  of  Oenothera  pratincola  are  not  alike. 
Each  zygote  is  formed  by  the  union  of  an  a  (female)  gamete  and  a  0  (male) 
gamete  (except  in  rare  cases  which  it  is  needless  to  mention  here)  and  has 
the  constitution  «£.     It,  in  turn,  produces  a  (female)  and  /3  (male)  gametes. 

2.  The  a  (female)  gametes  may  undergo  such  mutation  that,  unless 
certain  factors  for  flatness  are  present,  the  resulting  plants  are  revolute- 
leaved.    Such  mutated  gametes  are  designated  a. 

3.  The  |8  (male)  gametes  have  no  such  possibility  of  producing  revolute- 
leaved  plants. 

4.  Strain  C  carries  in  both  male  and  female  gametes,  but  not  in  the 
characteristic  a  and  |8  portions  of  the  gametes,  a  freely  segregating  factor 
for  flatness  (F),  in  the  presence  of  which  revoluteness  can  not  occur,  even 
though  the  mutation  to  a   has  occurred.     The  constitution  of  f.  typica 
strain  C  is  afiFF. 

5.  Strain  E  does  not  carry  in  either  male  or  female  gametes  the  inde- 
pendent factor  for  flatness  which  occurs  in  strain  C,  but  its  allelomorph 
(/).     The  constitution  of  f.  typica  strain  E  is  afiff. 

6.  Mut.  formosa,  a  revolute-leaved  mutation  thrown  by  strain  E,  differs 
from  f.  typica  strain  E  in  that  it  contains  a  mutated  a  (a).    The  constitu- 
tion of  mut.  formosa  is  a'Qff. 

7.  There  are  two  types  of  inheritance  going  on  simultaneously  and 
independently  in  Oenothera  pratincola,  matroclinic  inheritance,  connected 
with  certain  constant  differences  in  factorial  composition  between  male 
and  female  gametes,  and  Mendelian  inheritance,  connected  with  an  inde- 
pendent segregation  of  factors  carried  by  both  gametes. 

8.  The  cross  mut.  formosa  X  strain  C  (afiff  X  aftFF)  produces  only 
flat-leaved  plants  in  the  FI  generation;  in  the  F2  generation  there  occurs 
a  Mendelian  segregation  in  the  ratio  of  3  flat-leaved  plants  to  1  revolute 

GENETICS  6  :    Ja  1921 


14  FRIEDA  COBB 

leaved  plant.  This  segregation  has  been  followed  to  the  F4  generation. 
The  f .  typica  plants  descended  from  this  cross  have  the  constitution  afiFF 
or  a'0Ff,  and  are  called  f.  typica  M  (homozygous)  and  f.  typica  M  (hete- 
rozygous), respectively. 

9.  The  reciprocal  cross,  strain  C  X  mut.  formosa  (a$FF  X  a'pff)  also 
gives  only  flat-leaved  plants  in  the  Fi  generation;  but  in  the  F2  generation 
there  is  no  Mendelian  segregation,  though  there  occurs  by  mutation  a 
small  percentage  (1.6  percent)  of  revolute-leaved  plants.     In  this  cross 
the  inheritance  appears  to  be  matroclinic. 

10.  In  reciprocal  crosses  between  mut.  formosa  (a'pff)  and  f.  typica  E 
(apff)  the  inheritance  is  purely  matroclinic,  as  the  two  parents  are  alike  in 
regard  to  the  Mendelian  factors  for  flatness. 

11.  The  results,  recorded  in  the  tables  of  this  paper,  of  various  crosses 
between  f.  typica  M  and  f.  typica  C,  f.  typica  E  and  mut.  formosa  are  all  such 
as  to  favor  the  hypotheses  of  heterogametism  and  the  presence  of  a  pair 
of  Mendelian  factors  for  flatness  in  Oenotkera  pratincola.     All  the  results 
obtained  could  be  correctly  predicted  on  the  assumption  that: 

f .  typica  C       =  a@FF 
f .  typica  E       =  afiff 
mut.  formosa  —  a'ftfj 

12.  The  a  of  strain  C  may  become  mutated  to  a ',  but  in  pure  strain  C 
this  change  can  find  no  expression,  because  of  the  Mendelian  factors  for 
flatness  for  which  this  strain  is  homozygous.     That  the  change  does  some- 
times occur  here,  as  in  strain  E,  is  shown  by  the  occurrence  of  a  few  revo- 
lute-leaved plants  in  the  otherwise  uniformly  flat-leaved  F2  generation  of 
the  cross  f .  typica  C  X  mut.  formosa,  plants  in  which  the  a  portion  of  the 
constitution  came  from  strain  C  and  in  which  the  Mendelian  factors  for 
flatness  are  replaced  by  their  recessive  allelomorphs  from  strain  E. 

13.  The  difference,  with  regard  to  Mendelian  factors,  between  strains 
C  and  E  is  paralleled  by  the  difference,  with  regard  to  the  same  factors, 
between  mut.  nitidissima,  a  type  which  has  arisen  in  the  experiment 
garden,  and  strain  E  from  which  it  arose.     Strain  E  is  recessive;  mut. 
nitidissima  is  a  homozygous  dominant.     Evidently  a  homozygous  dom- 
inant strain  can  arise  from  a  homozygous  recessive  strain ;  the  reverse  proc- 
ess has  not  as  yet  been  known  to  take  place  in  the  garden. 

14.  It  is  concluded  that  mutation  may  be  masked  by  Mendelian  factors, 
and  that  the  apparent  induction  of  mutation   by  hybridization  may  be 
merely  the  first  appearance  of  changes  which  occurred  in  the  past  and 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA  15 

were  carried  on  unseen  until  their  appearance  in  the  zygote  was  made 
possible  by  the  removal,  through  hybridization,  of  inhibiting  Mendelian 
factors. 

LITERATURE  CITED 

BARTLETT,  H.  H.,  1915  a    Additional  evidence  of  mutation  in  Oenothera.    Bot.  Gaz.  59:  81- 

123. 
1915  b    Mass  mutation  in  Oenothera  pratincola.    Bot.  Gaz.  60:  425-456. 

COBB,  FRIEDA,  and  BARTLETT,  H.  H.,  1919  On  Mendelian  inheritance  in  crosses  between 
mass-mutating  and  non-mass-mutating  strains  of  Oenothera  pratincola.  Jour.  Wash- 
ington Acad.  Sci.  9:  462-483. 

DAVIS,  B.  M.,  1915  A  method  of  obtaining  complete  germination  of  seeds  in  Oenothera  and  of 
recording  the  residue  of  sterile  seed-like  structures.  Proc.  Nation.  Acad.  Sci.  1:  360- 
363. 

DE  VRIES,  HUGO,  1901,  1903    Die  Mutations-Theorie.    2  vols.,  xii  +  648  pp.;  xiv  +  752  pp. 

Leipzig:  Veit  &  Co. 

1915  a    The  coefficient  of  mutation  in  Oenothera  biennis  L.     Bot.   Gaz.  59:  169-196. 
1915  b    Oenothera  gigas  nanella,  a  Mendelian  mutant.     Bot.  Gaz.  60:  337-345. 

MORGAN,  T.  H.,  1918     Concerning  the  mutation  theory.     Sci.  Monthly  6:  385-405. 

MULLER,  H.  J.,  1918  Genetic  variability,  twin  hybrids  and  constant  hybrids,  in  a  case  of  bal- 
anced lethal  factors.  Genetics  3:  422-499. 

APPENDIX-TABLES 

Explanations  applying  to  all  of  the  tables 

In  table  1,  all  plants  not  otherwise  designated  were  f.  typica. 

F.  typica  M  is  the  synthetic,  Mendelian  strain  of  Oenothera  pratincola  which 
arises  from  the  cross  mut.  formosa  X  f.  typica  C  (or  other  form  with  equivalent 
pollen)  v 

The  numbers  in  columns  headed  "Key  number"  refer  to  corresponding 
numbers  in  table  1.  The  numbers  in  columns  headed  "Parent  plant"  are  the 
numbers  of  the  individual  plants  in  the  progenies  resulting  from  the  crosses  or 
self-pollinations  recorded  in  table  1. 

*  indicates  that  the  seeds  sown  were  from  a  single  capsule. 

t  indicates  that  seeds  from  two  or  more  capsules  were  sown  together. 

All  of  the  flat-leaved  types  mentioned  in  analyses  of  cultures  are  regularly 
thrown  by  self-pollinated  f.  typica  C,  and  some  of  them  also  by  f.  typica  E. 
All  of  the  revolute-leaved  types  mentioned  are  regularly  thrown  by  f.  typica  E 
and  by  mut.  formosa. 

Types  other  than  f.  typica,  mut.  latifolia,  and  mut.  formosa  mentioned  in  the 
following  tables  are: 

Mut.  albicans  (BARTLETT  1915  b,  page  449). 

Mut.  angustifolia  (BARTLETT  1915  b,  page  438). 

Mut.  dimorpha,  an  undescribed  mutation. 

Mut.  ericacea,  an  undescribed  mutation. 

Mut.  fallax,  an  undescribed  mutation,  as  a  seedling  very  much  like  mut. 
nummularia,  and  thrown  by  the  same  strains. 

GENETICS  6  :     Ja  1921 


16  FRIEDA  COBB 

Mut.  gigas  (BARTLETT  1915  b,  page  443). 

Mut.  grisea,  an  undescribed  mutation. 

Mut.  grisella,  an  undescribed  mutation. 

Mut.  nitidissima  (BARTLETT  1915  b,  page  440,  table  IV). 

Mut.  nummularia,  a  mutation  commonly  thrown  by  strain  C  but  never  by 
pure  strain  E.  (BARTLETT  1915  a,  page  97;  COBB  and  BARTLETT  1919.) 

Mut.  revoluta  (BARTLETT  1915  b,  page  450). 

Mut.  setacea  (BARTLETT  1915  b,  page  450). 

Mut.  sub-latifolia,  an  undescribed  mutation. 

Hyb.  mscida,  a  hybrid  of  Oenothera  pratincola  X  Oenothera  numismatica 
(BARTLETT  1915  a,  page  86).  This  form  is  like  Oe.  pratincola  f.  typica 
with  the  addition  of  the  viscid  pubescence  of  Oe.  numismatica. 

TABLE  1 

Record  of  the  parentage  of  all  of  the  progenies  recorded  in  the  following  tables  with  key  numbers. 
All  plants  not  otherwise  designated  are  f.  typica 

I2  E  -  5  -  199  formosa  -  28  formosa] 

X  [  4 

C  -  22  -  13  latifolia  -  87  latifolia} 


2    E  -  5  -  199  formosa  -  28  formosa 
X 

C  -  22  -  13  latifolia  -  87  latifolia 


190 


3  E  -  5  -  199  formosa  -  28  formosa} 

X  [  162 

C  -  22  -  13  latifolia  -  87  latifolia} 

4  E  -  5  -  199  formosa  -  28  formosa} 

X  f  162  -  164  formosa] 

C  -  22  -  13  latifolia  -  87  latifolia]          X 

C  -  52  -  6  grisella3  -  31  grisella  -  73  -  3J 
(=  3  No.  164  formosa  X  f.  typica  C) 

5  E  -  5  -  199  formosa  -  28  formosa} 

X  [  162  -  153  formosa] 

C  -  22  -  13  latifolia  -  87  latifolia}          X 

C  -  52  -  6  grisella  -  31  grisella  -  73  -  3J 
(=  3  No.  153  formosa  X  f.  typica  C) 

6  E  -  5  -  199  formosa  -  28  formosa] 

X  [  162  -  30  formosa] 

C  -  22  -  13  latifolia  -  87  latifolia}          X 

C  -  52  -  6  grisella  -  31  grisella  -  73  -  3J 
(=3  No.  30  formosa  X  f .  typica  C) 


2  These  numbers  are  designated  "key  numbers"  in  subsequent  tables. 
*  An  undescribed  mutation. 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PR  AT  IN  CO  LA  17 

TABLE  1  (continued) 

7  E  -  5  -  199  formosa  -  28  formosa} 

X  \  162  -  138  formosa] 

C  -  22  -  13  latifolia  -  87  latifolia}          X 

C  -  52  -  6  grisdla  -  31  grisdla  -  73  -  3j 
(=3  No.  138  formosa  X  L  typica  C) 

8  E  -  5  -  199  formosa  -  58  formosa  -  15  formosa} 

X  1 

C  -  52  -  6  groeKa  -  25  -  1  -  4lJ 

9  E  -  5  -  199  formosa  -  28  /omosa] 

X  [  162  -  164  formes*} 

C  -  22  -  13  latifolia  -  87  latifolia]          X  F  2  formosa 

E  -  43  -  89  -  5  -  19J         X 

C- 22 -7- 40 -5-9-2 
( =  23  No.  2  formosa  X  f .  typica  C) 


10  C  -  52  -  6  gr««//a  -  25  -  1  -  43  -  2 
E  -  5  -  199  formosa  -  58  formosa  -  15  /omosa]  X 

X  \  63  formosa} 

E  -  43  -  89  -  5  -  ij 
(  =  f  .  typica  C  X  25  No.  63  formosa) 

11  C  -  52  -  6  groetfa  -  25  -  1  -  43  -  19J 
E  -  5  -  199  formosa  -  58  formosa  -  14  formosa}         X          f 

X  I  27  formosa} 

E  -  43  -  89  -  5  -  l] 
(=  f.  ty#ca  C  X  25  No.  27  formosa} 


12 


c-  22  -7-40-5-9-1] 

X  ?•  27  formosa 

E  -  5  -  199  formosa  -  28  formosa  -  62  formosa} 


13  C  -  22  -  7  -  40  -  5  -  9  -  1 

E  -  5  -  199  formosa  -  28  formosa]  v 

X  [  162  -  164  formosa} 

C  -  22  -  13  latifolia  -  87  latifolia]  X  )•  16  formosa 

E  -  43  -  89  -  5  -  19j 
(=f.  typica  C  X  23  No.  16  formosa) 

14  C  -  52  -  6  grweKa  -  25  -  1  -  43  -  18] 
E  -  5  -  199  formosa  -  58  formosa  -  15  /orwosa]  X        > 

X  [  63  formosa} 

E  -  43  -  89  -  5  -  IJ 
(=  f.  ty#ca  C  X  25  No.  63  formosa) 


15  C  -  22  -  7  -  40  -  5  -  9  -  2] 

E  -  5  -  199  formosa  -  58  formosa  -  15  /0rw0sa]  X 

rwosaj 


X 

E  -  43  -  89  -  5  -  IJ 
(=  L  typica  C  X  25  No.  63  formosa) 


63  f 


GENETICS  6  :    Ja  1921 


18  FRIEDA  COBB 

TABLE  1  (continued) 


16  C  -  22  -  7  -  40  -  5  -  9  -  2 

E  -  5  -  199  formosa  -  28  formosa}  x 

X  [  162  -  164  formosa} 

C  -  22  -  13  latifolia  -  87  latifolia}         X  [  3  formosa 

E  -  43  -  89  -  5  -  19j 
(=  f.  typica  C  X  23  No.  3  formosa) 

17  E  -  5  -  199  formosa  -  58  formosa  -  35  formosa} 

X 
E  -  43  -  89  -  5  -  19J 

18  E  -  5  -  199  formosa  -  28  formosa} 

X  ^  162  -  153/0ri»<wa| 

C  -  22  -  13  latifolia  -  87  latifolia}          X 

E  -  43  -  72  -  5  -  6J 

(  =  3  No.  153  formosa  X  f.  ty#ca  E) 


19     E  -  5  -  199  formosa  -  28  /orwosal 

X  [  162  -  138  formosa} 

C  -  22  -  13  latifolia  -  87  latifolia}          X 

E  -  43  -  72  -  5  -  6 
(  =  3  No.  138  formosa  X  f.  fyp/ca  E) 


20    E  -  5  -  199  formosa  -  28  /omasa] 

X  [  162  -  164  formosa} 

C  -  22  -  13  /a/*y0/ia  -  87  latifolia]  X 

E  -  43  -  72  -  5  -  6J 
(=3  No.  164  formosa  X  f.  typica  E) 


21  E  -  5  -  199  formosa  -  28  formosa} 

X  \  162  -  30  formosa} 

C  -  22  -  13  latifolia  -  87  latifolia}          X 

E  -  43  -  89  -  5  -  ij 
(=  3  No.  30  formosa  X  1.  typica  E) 

22  E  -  5  -  199  formosa  -  58  formosa  -  14  /omosal 

X 
E  -  43  -  89 


-5-1 


23     E  -  5  -  199  formosa  -  28  /omoja 

X  }  162  -  164  formosa} 

C  -  22  -  13  latifolia  -  87  latifolia}          X 

E  -  43  -  89  -  5  -  19] 
(=3  No.  164  formosa  X  f.  /y#ca  E) 


24     E  -  5  -  199  formosa  -  28  /omosaj 

X  [4-22  formosa} 

C  -  22  -  13  Ja/i/b/ta  -  87  latifolia]          X 

E  -  43  -  89  -  5  -  19j 
(  =  1  No.  22  formosa  X  f  .  typica  E) 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA  19 

TABLE  1  (continued) 

25    E  -  5  -  199  formosa  -  58  formosa  -  15  formosa] 

X 
E  -  43  -  89  -  5  -  1 


26    E  -  5  -  199  formosa  -  28  formosa} 

X  j^  162  -  138  formosa] 

C  -  22  -  13  latifolia  -  87  latifolia}          X  \  21  formosa 

E  -  43  -  72  -  5  -  6j 
E  -  5  -  199  formosa  -  28  /orwosaj 

X  |  190  -  4  -  16 

C  -  22  -  13  toybWa  -  87  latifolia} 
(=  19  No.  21  formosa  X  2  No.  4  -  16  i.typica  M  (homozygous)) 


27  E  -  5  -  199  formosa  -  28 

X  [162-138  formosa] 

C  -  22  -  13  latifolia  -  87  latifolia}          X  [   14  formosa 

E  -  43  -  72  -  5  -  6] 
E  -  5  -  199  formosa  -  28  formosa] 

X  (•  190  -  4  -  21 

C  -  22  -  13  latifolia  -  87  latifolia} 
(=  19  No.  14  formosa  X  2  No.  4-21  f.  fy^z'ca  M  (homozygous)) 

28  E  -  5  -  199  formosa  -  28  /orfwwa] 

X  \  162  -  153  /0rwo.ya| 

C  -  22  -  13  latifolia  -  87  latifolia}          X  [  8  formosa 

E  -  43  -  72  -  5  -  6J 
E  -  5  -  199  formosa  -  28  formosa 

X  190-4-1 

C  -  22  -  13  latifolia  -  87  latifolia 
(=18  No.  8  formosa  X  2  No.  4  -  1  f.  typica  M  (homozygous)) 

29  E  -  5  -  199  formosa  -  28  formosa] 

X  [  162  -  153  /orwwa] 

C  -  22  -  13  /afo/ofoa  -  87  latifolia}          X  [  10  formosa 

E  -  43  -  72  -  5  -  6 
E  -  5  -  199  formosa  -  28  /om<«a] 

X  [  190  -  4  -  10 

C  -  22  -  13  latifolia  -  87  latifolia) 
(=  18  No.  10  formosa  X  2  No.  4  -  10  f.  typica  M  (homozygous)) 

30  E  -  5  -  199  formosa  -  58  formosa  -  15  formosa} 

X  |  69  formosa 

E  -  43  -  89  -  5  -  ll 
E  -  5  -  199  formosa  -  28  formosa 

X 

C  -  22  -  13  latifolia  -  87  latifolia 
(=  25  No.  69  formosa  X  2  No.  4  -  16  L  typica  M  (homozygous)) 


X 


X 
190  -  4  -  16 


GENETICS  6:    Ja  1921 


20  FRIEDA  COBB 

TABLE  1  (continued) 


31  E  -  5  -  199  formosa  -  28  formosa} 

X  }  4  -  164b] 

C  -  22  -  13  latifolia  -  87  latifolia]         X       \  2  formosa} 
E  -  43  -  89  -  5  -  1J        x         I 
E  -  5  -  199  formosa  -  28  formosal 

X  [  190  -  54  -  6J 

C  -  22  -  13  latifolia  -  87  latifolia} 
(=  55  No.  2  formosa  X  2  No.  54  -  6  i.typica  M  (homozygous)) 

32  E  -  5  -  199  formosa  -  28  /0n»<wa| 

X  [  190  -  54  -  3] 

C  -  22  -  13  latifolia  -  87  latifolia} 
E  -  5  -  199  formosa  -  28  formosa]  X 

X  [  4  -  164bl 

C  -  22  -  13  latifolia  -  87  latifolia]         X       f-  1  formosa} 

E  -  43  -  89  -  5  -  Ij 
(=  2  No.  54  -  3  f.  ty^'ca  M  (homozygous)  X  55  No.  1  formosa) 


33  E  -  5  -  199  formosa  -  28  formosa} 

X  \  190  -  54  -  6] 

C  -  22  -  13  latifolia  -  87  latifolia} 
E  -  5  -  199  formosa  -  28  formosa}  X 

X  \  4  -  164b] 

C  -  22  -  13  latifolia  -  87  latifolia}         X       \  1  formosa 

E  -  43  -  89  -  5  -  IJ 
(=2  No.  54  -  6  f.  ty/wa  M  (homozygous)  X  55  No.  1  formosa) 


34  E  -  5  -  199  formosa  -  28  formosa} 

X  [190-4-6 

C  -  22  -  13  latifolia  -  87  latifolia} 
E  -  5  -  199  formosa  -  28  formosa}  X 

X  [4-22  /or»Mwal 

C  -  22  -  13  latifolia  -  87  latifolia}          X  \  13  formosa 

E  -  43  -  89  -  5  -  19J 
(=  2  No.  4  -  6  i.typica  M  (homozygous)  X  24  No.  13  formosa) 

35  E  -  5  -  199  formosa  -  28  formosa} 

X  \  190  -  4  -  10 

C  -  22  -  13  /atf/b/ia  -  87  latifolia} 
E  -  5  -  199  formosa  -  28  formosa}  X 

X  \  162-  153  formosa} 

C  -  22  -  13  /atf/ofoa  -  87  latifolia}          X  \  10  formosa 

E  -  43  -  72  -  5  -  6J 
(=  2  No.  4  -  10  i.typica  M  (homozygous)  X  18  No.  10  formosa) 


36 


37 


MENDELIAN  INHERITANCE  IN  OENOTHERA  PRATINCOLA  1\ 

TABLE  1  (continued) 


E  -  5  -  199  formosa  -  28  formosa] 

X  \  190  -  4  -  15 

C-  22  -  13  latifolia  -  87  latifolia) 
E  -  5  -  199  formosa  -  28  formosa}  X 

X  [  162  -  153  formosa} 

C  -  22  -  13  latifolia  -  87  latifolia}          X  [  10  formosa 

E  -  43  -  72  -  5  -  6J 
(=  2  No.  4  -  15  i.typica  M  (homozygous)  X  18  No.  10  formosa) 

E  -  5  -  199  formosa  -  28  formosa} 

X  |  190  -  4  -  2 

C  -  22  -  13  latifolia  -  87  latifolia} 

E  -  5  -  199  formosa  -  28  formosa]  X 

X  [  162  -  153  formosa} 

tifolia) 


C  -  22  -  13  latifolia  -  87  latifoli 


X 


10  formosa 


38 


39 


40 


E  -  43  -  72  -  5  -  6j 
(=  2  No.  4  -  2  i.typica  M  (homozygous)  X  18  No.  10  formosa) 

E  -  5  -  199  formosa  -  28  formosa} 

X  \  190  -  4  -  21 

C  -  22  -  13  latifolia  -  87  latifolia) 
E  -  5  -  199  formosa  -  28  /omasa]  X 

X  j-  162  -  153  formosa} 

C  -  22  -  13  latifolia  -  87  latifolia]          X  }  10  formosa 

E  -  43  -  72  -  5  -  6J 
(=  2  No.  4  -  21  i.typica  M  (homozygous)  X  18  No.  10  formosa) 

E  -  5  -  199  formosa  -  28  formosa} 

X  [4-176-1 

C  -  22  -  13  latifolia  -  87  latifolia} 
E  -  5  -  199  formosa  -  28  formosa}  X 

X  \  162  -  30  formosa} 

C  -  22  -  13  latifolia  -  87  latifolia)          X  \  9  formosa 

E  -  43  -  89  -  5  -  1J 
(=  1  No.  176  -  1  i.typica  M  (homozygous)  X  21  No.  9  formosa) 


E  -  5  -  199  formosa  -  28  formosa} 

X  [4-176-13 

C  -  22  -  13  latifolia  -  87  latifolia) 
E  -  5  -  199  formosa  -  28  formosa]  X 

X  [  162  -  30  formosa} 

C  -  22  -  13  latifolia  -  87  latifolia)          X  \  9  formosa 

E  -  43  -  89  -  5  -  l] 
(=  1  No.  176  -  13  i.typica  M  (homozygous)  X  21  No.  9  formosa) 


41     E  -  5  -  199  formosa  -  28  formosa  -  31  /0 

E  -  5  -  199  formosa  -  28  formosa}      X 

X  }  4  -  62j 

C  -  22  -  13  latifolia  -  87  latifolia) 
(=  formosa  X  1  No.  62  i.typica  M  (heterozygous)) 


GENETICS  6  :    Ja  1921 


22 


FRIEDA  COBB 

TABLE  1  (continued) 


47 


42  E  -  5  -  199  formosa  -  58  formosa  -  15  formosa 

X 

E- 43  -89 -5-1 
E  _  5  _  199  formosa  -  58  formosa  -  44  formosa 

X 

CD  -  9  viscida4  -  26  wsotfa      -  11  viscida    -  24  wsc 
(=  25  No.  (&  formosa  X  wcwfa  M  (heterozygous)) 

43  E  -  5  -  199  formosa  -  58  formosa  -  15  formosa 

X 

E  -  43  -  89  -  5  -  1 
E  _  5  _  199  formosa  -  58  formosa  -  12  formosa 

X 

CD  -  9  viscida  -  26  viscida      -  11  viscida    -  24  viscida 
(=  25  No.  (&  formosa  X  wscwto  M  (heterozygous)) 

44  E  -  5  -  199  formosa  -  28  formosa} 

X  [  4  -  165] 

C  -  22  -  13  /a/tf0/»a  -  87  latifolia)  X  > 
E  -  5  -  199  formosa  -  28  formosa  -  62  formosa) 
(=  1  No.  165  i.typica  M  (heterozygous)  X  formosa) 

45  E  -  5  -  199  formosa  -  28  formosa} 

X  [  4  -  164b] 

C  -  22  -  13  Jatf/oWa  -  87  latifolia)      X 
E  -  5  -  199  formosa  -  28  formosa  -  31  formosa) 
(=   1  No.  164b  f .  fy^ica  M  (heterozygous)  X  formosa} 


68  formosa 

X 
6  viscida 


68  formosa 

X 
1  viscida 


X 


46  E  -  5  -  199  formosa  -  28  formosa} 

X  \  4  -  163bl 

C  -  22  -  13  latifolia  -  87  latifolia} 
E  -  5  -  199  formosa  -  28  /cmosa] 

X  f  4  -  33  formosa) 

C  -  22  -  13  te/»/0#a  -  87  latifolia) 
(=   1  No.  163b  i.typica  M  (heterozygous)  X  1  No.  33  formosa) 


E  -  43  -  89  -  5  -  1  -  21 
E  -  5  -  199  formosa  -  28  formosa}  X 

X  }  190  -  4  -  2j 

C  -  22  -  13  /a/t/0/ta  -  87  latifolia) 
(=  i.typica  E  X  2  No.  4  -  2  i.typica  M  (homozygous)) 


48    E  -  5  -  199  formosa  -  28 

X  4-64-9] 

C  -  22  -  13  /a/*/Wia  -  87  latifolia}         X 

E  -  43  -  74  -  41  -  45  -  2J 
(  =   1  No.  64  -  9  f  .  ty/wa  M  (homozygous)  X  f  .  ty^t'ca  E) 


4  A  hybrid  of  Oenothera  pratincola  X  Oe.  numismatica  (BARTLETT  1915  a,  p.  86).     This  form 
is  like  Oe.  pratincola  f.  typica  with  the  addition  of  the  viscid  pubescence  of  Oe.  numismatica. 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA  23 

TABLE  1  (continued) 


49    E  -  5  -  199  formosa  -  28  formosa} 

X  \  190  -  4  -  6] 

C  -  22  -  13  latifolia  -  87  latifolia]         X 

E  -  43  -  74  -  21  -  3J 
(  =  2  No.  4  -  6  f  .  ty/^'ca  M  (homozygous)   X  f  .  typka  E) 


50     E  -  5  -  199  formosa  -  28  formosa} 

X  }>  190  -  54  -  2] 

C  -  22  -  13  latifolia  -  87  latifolia}         X 

E  -  43  -  72  -  5  -  6  -  12J 
(=  2  No.  54  -  2  f.  typica  M  (homozygous)   X  f.  typica  E) 


51     E  -  5  -  199  formosa  -  28  formosa 


X 


190  -  4  -  2] 


X 


C  -  22  -  13  latifolia  -  87  latifolia 

E  -  43  -  89  -  5  -  1  -  6j 
(  =  2  No.  4  -  2  f  .  typica  M  (homozygous)   X  f  .  typica  E) 


52  E  -  5  -  199  formosa  -  28  /0jw<wal 

X  [4-176-1] 

C  -  22  -  13  latifolia  -  87  latifolia)         X 

E  -  43  -  74  -  21  -  3j 
(=   1  No.  176-1  i.  typica  M  (homozygous)  X  i.  typica  E) 

53  E  -  5  -  199  formosa  -  28  formosa] 

X  \  4-  1761 

C  -  22  -  13  /afo/ofoa  -  87  latifolia]       X        \ 
E  -  43  -  72  -  5  -  6j 
(=   1  No.  176  i.  typica  M  (homozygous)   X  i.  typica  E) 

54  E  -  5  -  199  formosa  -  28  formosa] 

X  \  4  -  1651 

C  -  22  -  13  /a/i/ofta  -  87  fcj^fllfej       X        }• 

E  -  43  -  89  -  5  -  ij 
(=   1  No.  165  i.  typica  M  (heterozygous)  X  f.  typica  E) 

55  E  -  5  -  199  formosa  -  28  formosa] 

X  \  4  -  164b] 

C  -  22  -  13  /afoyb&a  -  87  latifolia}       X 

E  -  43  -  89  -  5  -  ij 
(=   1  No.  164b  i.  typica  M  (heterozygous)  X  i.  typica  E) 

56  E  -  5  -  199  formosa  -  28  formosa} 

X  U  -  163b] 

C  -  22  -  13  /afo/o/ia  -  87  latifolia}       X 

E  -  43  -  89  -  5  -  IJ 
(=   1  No.  163b  L  typica  M  (heterozygous)  X  i.  typica  E) 


GENETICS  6:    Ja  1921 


24  FRIEDA  COBB 

TABLE  1  (continued) 


57    E  -  5  -  199  formosa  -  28  formosa} 

X  [  4  -  167b] 

C  -  22  -  13  latifolia  -  87  latifolia}       X          \ 
E  -  43  -  89  -  5  -  19J 
(=   1  No.  167b  i.typica  M  (heterozygous)  X  i.typica  E) 


58  E  -  5  -  199  formosa  -  28 

X  190-4-6 

C  -  22  -  13  latifolia  -  87  latifolia)         X  [ 

C  -  52  -  6  -  25  -  1  -  43  -  2J 
(=  2  No.  4  -  6  i.typica  M  (homozygous)  X  i.typica  C) 

59  E  -  5  -  199  formosa  -  28  formosa} 

X  [4-176] 

C  -  22  -  13  latifolia  -  87  latifolia}      X        [ 
C  -  22  -  7  -  40  -  5  -  2J 
(=1  No.  176  i.typica  M  (homozygous)  X  i.typica  C) 

60  E  -  5  -  199  formosa  -  28  formosa} 

X  [  4  -  167b] 

C  -  22  -  13  fo/J/bfta  -  87  latifolia}      X 

C  -  22  -  7  -  40  -  5  -  2j 
(=   1  No.  167b  i.typica  M  (heterozygous)  X  i.typica  O 


61  E  -  5  -  199  formosa  -  28 

X  4  -  165 

C  -  22  -  13  latifolia  -  87  latifolia}      X        [ 
C  -  22  -  7  -  40  -  5  -  2J 
(=  1  No.  165  i.typica  M  (heterozygous)  X  i.typica  C) 

62  E  -  5  -  199  formosa  -  28  formosa] 

X  [  4  -  163b] 

C  -  22  -  13  /a/#b&a  -  87  latifolia}      X 

C  -  22  -  7  -  40  -  5  -  2J 
(=  1  No.  163b  f.ty^ca  M  (heterozygous)  X  i.typica  C) 


63     E  -  5  -  199  formosa  -  28  formosa} 

X  [4-186  formosa 

C  -  22  -  13  /afc/o&a  -  87  latifolia} 

E  -  5  -  199  formosa  -  28  formosa} 

X  [4-166 

C  -  22  -  13  /a/#»  -  87  latifolia} 
(=   1  No.  186  formosa  X  1  No.  166  i.typica  M  (homozygous)) 


64    E  -  5  -  199  formosa  -  58  formosa  - 

X  r  69  formosa 

E  -  43  -  89  -  5  -  ij 
E  -  5  -  199  formosa  -  28  /omosa] 

X  [  190  -  4  -  16 

C  -  22  -  13  te/*/otax  -  87  latifolia} 
(=  25  No.  69  formosa  X  2  No.  4  -  16  i.typica  M  (homozygous)) 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA  25 

TABLE  1  (concluded) 


65  E  -  5  -  199  formosa  -  28  formosa] 


X  \  190  -  4  -  16] 

ifolia] 


C  -  22  -  13  to#0#d  -  87  latifol 
E  -  5  -  199  formosa  -  28  formosa}  X 

X  |  162  -  153  formosa} 

C  -  22  -  13  latifolia  -  87  latifolia]          X  [  x 

E  -  43  -  72  -  5  -  6j 
(=  2  No.  4  -  16  i.typica  M  (homozygous)  X   18  No.  x  formosa} 


66  E  -  5  -  199  formosa  -  28  / 

X  4  -  176] 

C  -  22  -  13  latifolia  -  87  latifolia]  X  | 
E  -  5  -  208  angustifolia  -  1  nitidissima*  -  15  formosa] 
(=  1  No.  176  i.typica  M  (homozygous)  X  formosa} 


See  BARTLETT  1915  b,  p.  440,  table  IV. 


GENETICS  6:    Ja  1921 


26 


FRIEDA  COBB 


TABLE  2 

A  classification  of  the  F3  generation  resulting  from  self-pollination  of  normal  f.  typica  plants  chosen 
at  random  from  the  segregating  F2  generation  of  the  cross  mut.formosa  X  mut.  latifolia  C.  (Male 
gametes  of  mitt,  latifolia  are  the  same  as  those  off.  typica  of  the  strain  from  which  it  arose). 


KEY 

NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

1 

No.  16 

370 

57 

42 

15 

2.80:1 

1 

No.  19 

319 

70 

64 

6 

10.67:1 

1 

No.  20 

598 

22 

19 

3 

6.33:1 

1 

No.  24 

492 

140 

112 

28 

4.00:1 

1 

No.  26 

448 

57 

45 

12 

3.75:1 

No.  28 

543 

40 

30 

10 

3.00:1 

No.  29 

578 

78 

62 

16 

3.88:1 

No.  32 

514 

44 

36 

8 

4.50:1 

No.  37 

243 

62 

42 

20 

2.10:1 

No.  43 

368 

98 

77 

21 

3.67:1 

No.  44 

299 

62 

53 

9 

5.89:1 

No.  47 

433 

132 

99 

33 

3.00:1 

No.  62 

209 

162 

125 

37 

3.38:1 

No.  154a 

227 

56 

38 

18 

2.11:1 

No.  155a 

316 

63 

40 

23 

1.74:1 

No.  156 

173 

43 

32 

11 

2.91:1 

No.  158 

278 

104 

84 

20 

4.20:1 

No.  161 

589 

99 

74 

25 

2.96:1 

No.  163b 

1,300 

48 

39 

9 

4.33:1 

No.  164b 

1,358 

229 

172 

57 

3.02:1 

No.  167a 

230 

47 

39 

8 

4.88:1 

No.  167b 

2,383 

246 

203 

43 

4.72:1 

No.  168 

598 

129 

95 

34 

2.80:1 

No.  171 

270 

108 

77 

31 

2.48:1 

No.  175 

518 

123 

93 

30 

3.10:1 

No.  177a 

178 

42 

32 

10 

3.20:1 

2 

No.  8 

255 

24 

22 

2 

11.00:1 

2 

No.  9 

338 

35 

26 

9 

2.89:1 

2 

No.  16 

517 

27 

22 

5 

4.40:1 

2 

No.  18 

506 

23 

15 

8 

1.87:1 

2 

No.  64 

545 

58 

38 

20 

1.90:1 

2 

No.  65 

562 

107 

73 

34 

2.15:1 

2 

No.  70 

334 

23 

17 

6 

2.83:1 

2 

No.  73 

567 

161 

105 

56 

1.87:1 

3 

No.  38 

350 

52 

37 

15 

2.47:1 

3 

No.  72 

472 

55 

46 

9 

5.11:1 

3 

No.  170 

343 

85 

61 

24 

2.54: 

3 

No.  183 

491 

33 

20 

13 

1.54: 

3 

No.  190 

455 

54 

33 

21 

1.57: 

3 

No.  198 

215 

21 

10 

11 

0.91: 

3 

No.  215 

460 

39 

35 

4 

8.75: 

Total 

20,242 

3,158 

9  ^84 

m' 

3fkO  .  1 

Z  jOO^ 

.(Jo.  1 

MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA 


27 


TABLE  2  (continued) 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO  . 

1 

No.  15 

179 

25 

25 

0 

No.  17 

437 

58 

58 

0 

No.  35 

441 

91 

91 

0 

No.  36 

493 

42 

42 

0 

No.  39 

379 

61 

61 

0 

No.  49 

370 

120 

120 

0 

No.  64 

371 

166 

166 

0 

No.  125 

401 

112 

112 

0 

No.  160a 

436 

47 

47 

0 

1 

No.  164a 

495 

116 

116 

0 

1 

No.  166 

582 

60 

60 

0 

1 

No.  176 

1,341 

191 

191 

0 

2 

No.   4 

220 

130 

130 

0 

2 

No.   5 

393 

112 

112 

0 

2 

No.   6 

243 

30 

30 

0 

2 

No.  17 

250 

51 

51 

0 

2 

No.  19 

229 

89 

89 

0 

2 

No.  54 

534 

219 

219 

0 

2 

No.  67 

595 

124 

124 

0 

3 

No.  75 

554 

239 

239 

0 

3 

No.  107 

306 

34 

34 

0 

3 

No.  169 

416 

48 

48 

0 

Total 

9,665 

2,165 

2,165 

0 

This  table  shows  the  presence  of  homozygous  and  heterozygous  dominants  in  the  F2  genera- 
tion. The  ratio  of  non-segregating  to  segregating  cultures  in  this  table  is  22:41,  which  closely 
approximates  the  expected  ratio,  1:2,  of  homozygous  to  heterozygous  dominants  in  the  F2 
generation. 


GENETICS  6  :    Ja  1921 


TABLE  3 

Analysis  of  the  F.  generation  resulting  from  self-pollination  off.  ty  pica  plants  chosen  at  random 
from  the  non-segregating  F3  progenies  (see  table  2)  of  the  cross  mut.  formosa  X  mut.  latifolia  C. 


KEY 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

EEVOLUTE- 
LEAVED 

RATIO 

NUMBER 

1 

No.    39-14 

ca.  l,300t6 

254 

254 

0 

No.    39-24 

ca.  l,100t 

167 

167 

0 

No.    64-9 

ca.  l,000t 

109 

109 

0 

No.  125-44 

ca.     750f 

18 

18 

0 

No.  125-46 

ca.     900f 

85 

85 

0 

No.  125-48 

ca.     800f 

14 

14 

0 

No.  125-49 

ca.     850f 

26 

26 

0 

No.  166-9 

ca.  l,200t 

10 

10 

0 

1 

No.  176-1 

ca.     700f 

20 

20 

0 

1 

No.  176-13 

ca.     900f 

51 

51 

0 

2 

No.      4-2 

ca.     900f 

47 

47 

0 

2 

No.      4-3 

ca.     800f 

78 

78 

0 

2 

No.      4-6 

ca.     700f 

15 

15 

0 

2 

No.      4-16 

ca.  l,200f 

138 

138 

0 

2 

No.      4-21 

ca.     700f 

69 

69 

0 

2 

No.    54-6 

ca.     600f 

13 

13 

0 

Total.  . 



ca.  14,400 

1,114 

1,114 

0 

All  of  the  plants  are  flat-leaved,  demonstrating  further  the  presence  of  homozygous  domi- 
nants in  the  F2  generation  of  the  cross.  Of  the  326  plants  grown  to  maturity,  taken  in  part 
from  each  of  twelve  cultures,  320  proved  to  be  f.  typica  and  of  the  remaining  6  plants  2 
were  mut.  nummularia,7  2  were  mut.  fallax,  an  undescribed  mutation,  as  a  seedling  very  much 
like  mut.  nummularia  and  thrown  by  the  same  strains,  1  was  probably  mut.  gigas*  and  1 
resembled  mut.  angustifolia.9 

TABLE  4 

Analysis  of  the  F*  generation  resulting  from  self-pollination  of  f.  typica  plants  chosen  at  random 
from  the  segregating  F3  progenies  (see  table  2)  of  the  cross  mut.  formosa  X  mut.  latifolia  C. 


KEY 

NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

1 
1 

No.  167b-12 
No.  167b-25 

ca.     550f 
ca.     900f 

15 
165 

10 
132 

5 
33 

2.00:1 
4.00:1 

Total 

ca.  l,450f 

180 

142 

38 

3  74'  1 

1 

No.  168-14 

ca.     700f 

25 

25 

0 

Of  the  three  cultures,  two  are  segregating  and  one  is  not,  showing  the  presence  of  homozygous 
and  heterozygous  dominants  in  the  F3  generation  from  heterozygous  Fj  plants.  Of  the  64  plants 
grown  to  maturity  from  the  two  segregating  cultures  52  proved  to  be  f.  typica,  1  was  mut.  fallax, 
10  were  mut.  formosa,  and  1  was  mut.  setacea,10  which  is  a  revolute-leaved  type  thrown  by  mut. 
formosa.  All  of  the  25  plants  of  the  non-segregating  culture  proved  to  be  f .  typica. 

6  In  this  and  subsequent  tables  the  dagger  (f)  indicates  that  seeds  from  two  or  more  capsules 
were  sown  together. 

7  Mut.  nummularia,  a  mutation  commonly  thrown  by  strain  C,  but  never  by  pure  strain  E 
See  BARTLETT  1915  a,  p.  97;  COBB  and  BARTLETT  1919. 

8  See  BARTLETT,  1915  b,  p.  443. 

9  See  BARTLETT,  1915  b,  p.  438. 

10  See  BARTLETT  ,  1915  b,  p.  450. 


GENKTICS  6  :  28    Ja  1921 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA 


29 


TABLE  5 
Analysis  of  the  FI  generation  of  the  cross  mut.  formosa  X/.  typica  C  (a'0ff  X  apFF). 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

4 

ca.  300f 

7 

7 

0 

5 

316f 

10 

10 

0 

6 

51*u 

8 

8 

0 

7 

327f 

28 

28 

0 

8 

57f 

30 

30 

0 

9 

33* 

17 

17 

0 

Total.. 

1,084 

100 

100 

0 

The  cultures  consist  of  flat-leaved  types  only,  but  as  seedlings  the  plants  show  the  effect  of 
crossing  in  irregularities  in  their  leaves,  the  blades  being  unsymmetrically  developed.  Of  the 
95  plants  grown  to  maturity,  taken  in  part  from  each  of  the  six  cultures,  all  proved  to  be  f .  typica 
except  1  plant,  which  was  an  undescribed  flat-leaved  mutation,  mut.  dimorpha. 


TABLE  6 


Analysis  of  the  F2  generation  resulting  from  self-pollination  of  f.  typica  plants  chosen  at  random 
from  the  FI  generation  (see  table  5)  of  the  cross  mut.  formosa  X/.  typica  C  (a'ftjfX  a&FF). 
Each  of  the  cultures  contains  both  flat-leaved  and  revolute-leaved  plants  in  approximately  a  3:1 
ratio. 


KEY 

NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

4 

No.    3 

ca.     500f 

165 

132 

33 

4.00:1 

4 

No.    5 

ca.     850f 

67 

54 

13 

4.15:1 

4 

No.    6 

ca.     900f 

452 

337 

115 

2.93:1 

5 

No,    7 

ca.     700f 

87 

69 

18 

3.83:1 

5 

No.    9 

ca.     800f 

346 

243 

103 

2.36:1 

6 

No.    1 

ca.     600f 

208 

155 

53 

2.92:1 

6 

No.    3 

ca.     800f 

121 

86 

35 

2.46: 

6 

No.    6 

ca.  l,000f 

111 

81 

30 

2.70: 

6 

No.    7 

ca.  l,000f 

483 

347 

136 

2.55: 

6 

No.    8 

ca.     900f 

244 

181 

63 

2.87: 

7 

No.    4 

ca.     800f 

.286 

220 

66 

3.33: 

7 

No.    6 

ca.     900t 

202 

141 

61 

2.31: 

7 

No.    9 

ca.     900t 

182 

120 

62 

1.94: 

7 

No.  10 

ca.     900t 

200 

146 

54 

2.70: 

8 

No.  10 

ca.     950t 

120 

87 

33 

2.64: 

Total 

ca.  12,500 

3,274 

2,399 

875 

2.74:1 

11  The  asterisk  (*)  in  this  and  subsequent  tables  indicates  that  seeds  from  a  single  capsule 
were  sown. 


GENETICS  6  :     Ja  1921 


30 


FRIEDA  COBB 


TABLE  7 
Analysis  of  the  FI  generation  of  the  cross  f.  typica  C  X  mut.formosa  (a@FF  X  ot' 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS   PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

10 

lOOf 

63 

63 

0 

11 

221* 

50 

50 

0 

12 

140* 

88 

88 

0 

13 

* 

45 

45 

0 

14 

186* 

125 

125 

0 

15 

t 

176 

176 

0 

16 

300f 

235 

235 

0 

Total.  . 

947+ 

782 

782 

0 

The  cultures  consist  of  flat-leaved  types  only.  Of  the  389  plants  grown  to  maturity,  taken 
in  part  from  each  of  the  seven  cultures,  381  were  f.  typica,  and  the  remaining  8  were  of  other 
flat-leaved  types — 3  of  mut.  fallax,  2  of  mut.  dimorpha,  1  of  mut.  grisella  (an  undescribed 
mutation),  and  2  undetermined  mutations. 


TABLE  8 

Analysis  of  the  F2  generation  resulting  from  self-pollination  of  f.  typica  plants  chosen  at  random 
.    from  the  FI  generation  (see  table  7}  of  the  cross  f.  typica  C   X  mut.  formosa  (a@FF  X  a'pff). 


KEY 

NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

10 

No.    1 

l,296f 

545 

533 

12 

10 

No.    2 

l,425f 

92 

92 

0 

10 

No.  17 

810f 

174 

174 

0 

10 

No.  25 

681f 

18 

17 

1 

10 

No.  42 

l,113f 

142 

142 

0 

11 

No.  32 

l,265f 

41 

41 

0 

11 

No.  35 

l,243f 

17 

16 

1 

11 

No.  37 

l,428f 

29 

26 

3 

11 

No.  44 

l,812f 

8 

7 

1 

11 

No.  50 

l,574f 

57 

54 

3 

12 

No.  12 

l,455f 

3 

2 

1 

12 

No.  14 

l,693f 

127 

126 

1 

12 

No.  29 

l,594f 

5' 

4 

1 

12 

No.  36 

l,214f 

87 

86 

1 

12 

No.  44 

l,232f 

309 

308 

1 

Total 

19,835 

1,654 

1,628 

26 

61.5:1 

The  cultures  consist  of  flat-leaved  plants  with  a  small  percentage  of  revolute-leaved  plants, 
considered  to  have  arisen  by  separate  mutations  of  the  a  gamete  in  the  presence  of  the  recessive 
allelomorphs  of  the  Mendelian  factors  for  flatness. 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA 


31 


TABLE  9 
Analysis  of  the  FI  generation  of  the  cross  mut.  formosa  X  /.  typica  E  (a'0ff  X  afiff). 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

17 

258f 

21 

0 

21 

18 

471f 

10 

0 

10 

19 

535f 

86 

0 

86 

20 

157* 

10 

0 

10 

21 

150* 

13 

0 

13 

22 

167* 

33 

0 

33 

23 

100* 

21 

0 

21 

24 

138* 

25 

0 

25 

25 

866f 

86 

0 

86 

Total 

2842 

305 

o 

305 

All  of  the  plants  are  revolute-leaved.  Of  the  235  plants  grown  to  maturity,  taken  in  part 
from  each  of  the  nine  cultures,  230  were  mut.  formosa,  and  the  remaining  5  were  plants  of  other 
revolute-leaved  types — 3  of  mut.  revoluta,12  1  of  mut.  setacea,  and  1  of  mut.  albicans  (?),13  all 
of  these  being  types  thrown  by  pure  strains  of  mut.  formosa. 


TABLE  10 

Analysis  of  the  FZ  generation  resulting  from  self-pollination  of  f.  typica  plants  chosen  at  random 
from  the  FI  generation  (see  table  9}  of  the  cross  mut.  formosa  X  f.  typica  E  (a'ftjf  X  a&ff). 


KEY 

NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

22 

No.  24 

ca.     800f 

260 

0 

260 

23 

No.    2 

ca.     600f 

111 

0 

111 

25 

No.  63 

ca.     800f 

216 

0 

216 

18 

No.    8 

ca.     750f 

41 

0 

41 

Total.  . 

ca.  2,950 

628 

0 

628 

All  of  the  plants  are  revolute-leaved,  as  in  the  FI  generation  of  this  cross;  that  is,  the  inher- 
itance is  matroclinic.  Of  the  72  plants  grown  to  maturity,  taken  in  part  from  each  of  the  four 
cultures,  all  proved  to  be  mut.  formosa. 

12  See  BARTLETT,  1915  b,  p.  450. 

13  See  BARTLETT,  1915  b,  p.  449. 


GENETICS  6  :    Ja  1921 


32 


FRIEDA  COBB 


TABLE  11 

Analysis  of  the  FI  generation  of  the  cross  mut.  formosa  X  /.  typica  M  (homozygous)  (a'ftff  X  a'pFF). 
The  staminate  parent  belonged  to  the  F3  generation  of  the  cross  mut.  formosa  X  mut.  latifolia  C. 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

26 

153f 

113 

113 

0 

27 

225f 

69 

69 

0 

28 

56* 

12 

12 

0 

29 

79* 

30 

30 

0 

30 

152f 

26 

26 

0 

31 

I67f 

42 

42 

0 

Total.  . 

832 

292 

292 

0 

Each  culture  contains  only  flat-leaved  plants.  Of  the  181  plants  grown  to  maturity,  taken 
in  part  from  each  of  the  six  cultures,  160  proved  to  be  f.  typica,-  and  the  remaining  21  were  of 
other  flat-leaved  types — 16  were  mut.  dimorpha,  1  was  mut.  fallax,  1  was  mut.  grisea  (an 
undcscribed  mutation),  and  3  were  undetermined. 

TABLE  12 

Analysis  of  the  F2  generation  resulting  from  self-pollination  of  f.  typica  plants  chosen  at  ran- 
dom from  the  F\  generation  (see  table  11)  of  the  cross  mut.  formosa  X  /.  typica  M  (homozygous) 
(a'jSJfX  a'(3FF).  Each  of  the  cultures  contains  flat-leaved  and  revolute-leaved  plants  in  approx- 
imately a  3:1  ratio. 


KEY 

RKVOLUTK- 

NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

LEAVED 

RATIO 

26 

No.  41 

ca.  l,400f 

95 

71 

24 

2.96: 

26 

No.    3 

ca.  2,000t 

245 

166 

79 

2.10: 

26 

No.    9 

ca.  l,200f 

62 

46 

16 

2.87: 

26 

No.  25 

ca.  l,200f 

34 

23 

11 

2.09: 

26 

No.  46 

ca.  2,  lOOf 

61 

39 

22 

1.77: 

27 

No.    3 

ca.  2,200f 

31 

22 

9 

2.44:1 

27 

No.  15 

ca.  2,050f 

23 

20 

3 

6.67:1 

27 

No.  16 

ca.  2,050f 

51 

32 

19 

1.68:1 

27 

No.  20 

ca.  2,l(X)t 

28 

21 

7 

3.00:1 

29 

No.    6 

ca.  l,500t 

73 

54 

19 

2.84:1 

29 

No.  12 

ca.  l,150f 

25 

20 

5 

4.00:1 

29 

No.  16 

ca.  l,100t 

282 

216 

66 

3.27: 

29 

No.  18 

ca.  l,650f 

112 

84 

28 

3.00: 

29 

No.  25 

ca.  l,650t 

120 

68 

52 

1.31: 

31 

No.    4 

ca.  l,800f 

126 

92 

34 

2.71: 

31 

No.    6 

ca.  l,900t 

86 

56 

30 

1.87: 

63 

No.    1 

ca.  8,900f 

993 

742 

251 

2.96: 

63 

No.    2 

ca.  4,600f 

849 

655 

194 

3.38:1 

63 

No.    3 

ca.  l,450f 

563 

423 

140 

3.02:1 

63 

No.    4 

ca.  l,500t 

77 

59 

18 

3.28:1 

64 

No.  13 

ca.  2,300f 

81 

62 

19 

3.26:1 

64 

No.  15 

ca.  2,500f 

229 

158 

71 

2.23:1 

64 

No.  17 

ca.  2,  lOOf 

73 

46 

27 

1.70:1 

64 

No.  23 

ca.  2,000t 

300 

212 

88 

2.41:1 

64 

No.  24 

ca.  2,300t 

718 

508 

210 

2.42:1 

Total 

ca.  54,700 

5,337 

3,895 

1,442 

2.70:1 

TABLE  13 
Analysis  of  the  FI  generation  of  the  cross  f.  typica  M  (homozygous)  X  mul.formosa  (a'QFF  X  a'pjf). 


KEY 

NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
'  LEAVED 

RATIO 

32 

ca.  300f 

48 

48 

0 

33 

293f 

122 

122 

0 

34 

202J 

18 

18 

0 

35 

220f 

27 

27 

0 

36 

50* 

33 

33 

0 

37 

66f 

45 

45 

0 

38 

204f 

122 

122 

0 

39 

182f 

23 

23 

0 

40 

71t 

36 

36 

0 

Total 

ca.  1,588 

474 

474 

o 

The  pistillate  parent  belonged  to  the  Fa  generation  of  the  cross  mut.  formosa  X  mut.  lati- 
folia  C.  Each  of  the  cultures  consists  of  only  flat-leaved  plants.  Of  the  210  plants  grown  to 
maturity,  taken  in  part  from  each  of  the  nine  cultures,  204  proved  to  be  f.  typica,  and  the 
remaining  6  were  of  other  flat-leaved  types, — 3  were  mut.  dimorpha,  1  was  mut.  fallax,  1  was 
mut.  sub-latifolia  (?),14  and  1  was  undetermined. 

TABLE  14 

Analysis  of  the  F2  generation  resulting  from  self-pollination  of  f.  typica  plants  chosen  at  random 
from  the  FI  generation  (see  table  13)  of  the  cross  f.  typica  M  (homozygous)  X  mut.  formosa 
X  a'Qff). 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

32 

No.    3 

ca.  l,750f 

64 

46 

18 

2.56: 

32 

No.    4 

ca.  l,700f 

203 

155 

48 

3.23: 

34 

No.    7 

ca.  l,900f 

122 

92 

30 

3.07: 

34 

No.    9 

ca.  l,650t 

78 

63 

15 

4.20: 

34 

No.  13 

ca.  l,950f 

739 

549 

190 

2.89: 

35 

No.    4 

ca.  l,600f 

111 

72 

39 

1.85: 

35 

No.    7 

ca.  l,275t 

556 

406 

150 

2.71: 

35 

No.  11 

ca.  l,600f 

34 

23 

11 

2.09:1 

37 

No.  11 

ca.  2,150t 

147 

109 

38 

2.87:1 

37 

No.  16 

l,353f 

38 

31 

7 

4.43:1 

37 

No.  21 

ca.  l,850f 

159 

120 

39 

3.08:1 

37 

No.  23 

l,103f 

54 

40 

14 

2.86: 

38 

No.    5 

ca.  l,900t 

110 

78 

32 

2.44: 

38 

No.    6 

ca.  l,900f 

380 

283 

97 

2.92: 

38 

No.  24 

ca.  2,600f 

443 

312 

131 

2.38: 

65 

No.    1 

ca.  l,400f 

210 

143 

67 

2.13: 

65 

No-.    4 

ca.  l,450f 

159 

109 

50 

2.18: 

66 

No.    1 

ca.     700f 

225 

150 

75 

2.00: 

66 

No.    2 

ca.     700f 

34 

26 

8 

3.25: 

66 

No.    3 

ca.  l,600f 

434 

313 

121 

2.59: 

Total 

ca.  32,131 

4,300 

3,120 

1,180 

2.64:1 

Each  of  the  cultures  contains  both  flat-leaved  and  revolute-leaved  plants,  in  approximately 
a  3 : 1  ratio.  Of  the  74  plants  from  three  of  these  cultures,  grown  to  maturity,  58  proved  to  be 
f .  typica  and  16  proved  to  be  mut.  formosa. 

14  An  undescribed  mutation. 


GENETICS  6 :  33    Ja  1921 


34 


FRIEDA  COBB 


TABLE  15 
Analysis  of  the  FI  generation  of  the  cross  mut.formosa  X  /.  typica  M  (heterozygous]  (a'@ff  X 


KEY 

NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

41 

333f 

13 

5 

8 

0.63:1 

42 

64* 

27 

15 

12 

1.25:1 

43 

40* 

19 

7 

12 

0.58:1 

Total.. 

437 

59 

27 

32 

0.84:1 

In  the  case  of  41,  the  staminate  parent  belonged  to  the  F2  generation  of  the  cross  mut.  for- 
mosa  X  mut.  latifolia  C;  in  the  case  of  42  and  43  to  the  F2  generation  of  the  cross  mut.  formosa 
X  hyb.  viscida.15  In  each  of  the  cultures  flat-leaved  and  revolute-leaved  plants  occur,  in  about 
equal  numbers.  The  expected  ratio  is  1:1.  When  the  germination  is  poor,  the  number  of 
revolute-leaved  plants  often  slightly  exceeds  the  expectation,  as  it  does  here.  Of  the  42  plants 
grown  to  maturity,  taken  in  part  from  each  of  the  three  cultures,  21  were  f.  typica  (one  of  them 
a 'dwarf),  3  were  of  other  flat-leaved  types  (2  of  mut.  graminea,16  and  1  an  undetermined  muta- 
tion), 16  were  mut.  formosa  (6  of  them  very  poor  plants)  and  2  were  mut.  revoluta,  which  is  one 
of  the  revolute-leaved  mutations  thrown  by  mut.  formosa. 


TABLE  16 

Analysis  of  an  FZ  progeny  resulting  from  self-pollination  of  an  f.  typica  plant  of  the  FI 
(see  table  15}  of  the  cross  mut.formosa  X  /.  typica  M  (heterozygous}  (a'fiff  X  a'pFf). 
bers  of  flat-leaved  and  revolute-leaved  plants  closely  approximate  a  3:1  ratio. 


generation 
The  num- 


KEY 

NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

41 

No.  10 

ca.  4,250f 

1,849 

1,348 

501 

2.69:1 

TABLE  17 
Analysis  of  the  F\  generation  of  the  cross  f.  typica  M  (heterozygous]  X  mut.formosa  (a'fiFf  X  oi' 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

44 
45 

657f 
319f 

117 

50 

58 

20 

59 
30 

1.98:1 
0.67:1 

Total  .  . 

976 

167 

78 

89 

0  88:1 

The  pistillate  parent  belonged  to  the  F2  generation  of  the  cross  mut.  formosa  X  mut.  lati- 
folia C.  In  these  cultures  flat-leaved  and  revolute-leaved  plants  occur  in  about  equal  numbers, 
but,  as  in  the  reciprocal  cross,  the  number  of  revolute-leaved  plants  slightly  exceeds  that  required 
for  the  expected  1 : 1  ratio.  Of  the  88  plants  grown  to  maturity,  taken  in  part  from  each  of  the 
two  cultures,  36  were  f.  typica,  2  were  of  other  flat-leaved  types  (1  of  mut.  ericacea17  and  1  dwarf), 
and  50  were  mut.  formosa,  one  of  them  bearing  a  flat-leaved  bud-sport. 

15  Hyb.  viscida,  a  hybrid  of  Oenothera  pratincola  X  Oe.  numismatica  (see  BARTLETT  1915  a, 
p.  86).     This  form  is  like  Oe.  pratincola  L  typica  with  the  addition  of  the  viscid  pubescence 
of  Oe.  numismatica. 

16  Regarding  mut.  graminea,  see  BARTLETT  1915  b,  p.  429. 

17  An  undescribed  mutation. 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA 


35 


TABLE  18 


Analysis  of  the  F2  generation  resulting  from  self-pollination  off.  typica  plants  chosen  at  random 
from  the  Fi  generation  (see  table  17)  of  the  cross  f.  typica  M  (heterozygous)  X  mut.  formosa 


KEY 

NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

RE  VOLUTE  - 
LEAVED 

RATIO 

45 

No.  12 

ca.     750f 

157 

114 

43 

2.65:1 

46 

No.    2 

ca.     600f 

22 

16 

6 

2.66:1 

44 

No.  14 

ca.     900t 

18 

14 

4 

3.50:1 

44 

No.  17 

ca.     800f 

463 

344 

119 

2.89:1 

Total.  . 

ca.  3,050 

660 

488 

172 

2.84:1 

Each  of  the  cultures  contains  both  flat-leaved  and  revolute-leaved  plants,  in  approximately 
a  3 : 1  ratio.  Of  the  50  plants  from  one  culture  grown  to  maturity,  42  proved  to  be  f .  typica 
and  8  proved  to  be  mut.  formosa. 

TABLE  19 
Analysis  of  an  FI  progeny  of  the  cross  f.  typica  EXf.  typica  M  (homozygous)  (aftf  X  a'pFF). 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

47 

95f 

78 

78 

0 

The  staminate  parent  belonged  to  the  F3  generation  of  the  cross  mut.  formosa  X  mut.  lati- 
folia  C.  All  of  the  plants  are  flat-leaved.  Of  the  49  plants  grown  to  maturity,  44  were  f .  typica, 
and  the  remaining  5  were  of  other  flat-leaved  types — 2  of  mut.  ericacea,  2  of  mut.  dimorpha,  and 
1  undetermined  mutation. 


TABLE  20 


Analysis  of  the  F2  generation  resulting  from  self-pollination  of  f.  typica  plants  chosen  at  ran- 
dom from  the  Ft  generation  (see  table  19)  of  the  cross  f.  typica  EXf.  typica  M  (homozygous) 
(aftff  X  a'pFF).  In  each  culture  all  of  the  plants  are  flat-leaved. 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

47 

No.    4 

ca.  l,700t 

1,016      • 

1,016 

0 

47 

No.    8 

ca.  l,800t 

1,265 

1,265 

0 

47 

No.  11 

ca.  l,000t 

813 

813 

0 

47 

No.  15 

l,205f 

91 

91 

0 

47 

No.  19 

ca.  l,400f 

1,140 

1,140 

0 

47 

No.  26 

l,436f 

1,062 

1,062 

0 

47 

No.  28 

ca.  1,500| 

533 

533 

0 

47 

No.  30 

l,214f 

169 

169 

0 

Total   . 

ca.  11,255 

6,089 

6,089 

0 

GENETICS  6:    Ja  1921 


36 


FRIEDA  COBB 


TABLE  21 
Analysis  of  the  Fi  generation  of  the  cross  f.  typica  M  (homozygous)  X  /.  typica  E  (a'fiFF  X  aft/). 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

48 

194f 

21 

21 

0 

49 

392f 

238 

238 

0 

50 

197f 

128 

128 

0 

51 

361f 

275 

275 

0 

52 

50f 

32 

32 

0 

Total.. 

1.194 

694 

694 

0 

The  pistillate  parent  belonged  to  the  F3  generation  of  the  cross  mut.  formosa  X  mut.  lati- 
folia  C.  Each  of  the  cultures  contains  only  flat-leaved  plants.  Of  the  157  plants  grown  to 
maturity,  taken  in  part  from  each  of  the  five  cultures,  155  proved  to  be  f.  typica,  and  the  remain- 
ing 2  were  mut.  fallax. 


TABLE  22 

Analysis  of  the  F*  generation  resulting  from  self-pollination  of  f.  typica  plants  chosen  at  ran- 
dom from  the  FI  generation  (see  table  21)  of  the  cross  f.  typica  M  (homozygous)  X/.  typica  E 
(a'0FF  X  aftff). 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

50 

No.  40 

l,425f 

629 

465 

164 

2.84:1 

50 

No.  44 

l,529f 

461 

337 

124 

2.72:1 

51 

No.  12 

l,345f 

612 

445 

167 

2.66:1 

53 

No.    1 

ca.  l,000t 

494 

367 

127 

2.88:1 

53 

No.    2 

ca.     900t 

31 

23 

8 

2.88:1 

53 

No.    3 

ca.  l,000f 

17 

12 

5 

2.40:1 

53 

No.    4 

ca.     750f 

10 

7 

3 

2.33:1 

53 

No.    5 

ca.     400f 

33 

22 

11 

2.00:1 

53 

No.    6 

ca.     900f 

12 

11 

1 

11.00:1 

Total  .  . 

ca.  9,249 

2299 

1  689 

610 

7   77.1 

Each  of  the  cultures  contains  flat-leaved  and  revolute-leaved  plants,  in  approximately  a  3:1 
ratio.  Of  the  25  plants  from  one  culture  grown  to  maturity,  22  proved  to  be  f.  typica,  1  was 
of  another  flat-leaved  type  (mut.  dimorpha),  and  2  were  mut.  formosa. 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA 


37 


TABLE  23 
Analysis  of  the  FI  generation  of  the  cross  f.  typica  M  (heterozygous]  X  /.  typica  E  (a'pFf  X  cfifi). 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

54 

528f 

42 

20 

22 

0.91:1 

55 

401f 

12 

6 

6 

1.00:1 

56 

430f 

86 

34 

52 

0.65:1 

57 

301f 

34 

22 

12 

1.83:1 

Total.  . 

1,660 

174 

82 

92 

0  80  '1 

The  pistillate  parent  belonged  to  the  F2  generation  of  the  cross  mut.  formosa  X  mut.  lati- 
folia  C.  In  each  of  the  cultures  flat-leaved  and  revolute-leaved  plants  occur  in  about  equal 
numbers.  The  expected  ratio  is  1:1.  When  the  germination  is  poor,  the  number  of  revolute- 
leaved  plants  often  slightly  exceeds  the  expectation,  as  it  does  here.  Of  the  112  plants  grown 
to  maturity,  taken  in  part  from  each  of  the  four  cultures,  56  were  f.  typica,  4  were  of  other 
flat-leaved  types  (1  was  mut.  fallax  and  3  were  of  a  dwarf  type),  51  were  mut.  formosa,  and  1 
was  mut.  revoluta,  which  is  one  of  the  revolute-leaved  mutations  thrown  by  mut.  formosa. 


TABLE  24 

Analysis  of  the  F%  generation  resulting  from  self-pollination  of  f.  typica  plants  chosen  at  ran- 
dom from  the  FI  generation  (see  table  23)  of  the  cross  f.  typica  M  (heterozygous)  X  /.  typica  E 
aft/). 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE 
LEAVED 

RATIO 

54 

No.    3 

ca.     900f 

198 

153 

45 

3.40:1 

57 

No.  20 

ca.  l,000f 

228 

167 

61 

2.74:1 

57 

No.  22 

ca.  l,000t 

55 

41 

14 

2.93:1 

57 

No.  24 

ca.     800f 

12 

10 

2 

5.00:1 

57 

No.  25 

ca.     500f 

101 

79 

22 

3.59:1 

57 

No.  28 

ca.     750t 

107 

86 

21 

4.10:1 

Total 

ca.  4,950 

701 

536 

165 

3.25:1 

Each  of  the  cultures  contains  both  flat-leaved  and  revolute-leaved  plants  in  approximately  a 
3 : 1  ratio.  Of  the  49  plants  from  one  culture  grown  to  maturity,  34  proved  to  be  f .  typica  and 
15  proved  to  be  mut.  formosa. 


GENETICS  6  :    Ja  1921 


38 


FRIEDA  COBB 


TABLE  25 
Analysis  of  the  FI  generation  of  the  cross  f.  typica  M  (homozygous)  X  /.  typica  C  (a'pFF  X  apFF). 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

58 

82* 

57 

57 

0 

59 

109f 

11 

11 

0 

Total.. 

191 

68 

68 

0 

The  pistillate  parent  belonged  to  the  F2  generation  (in  the  case  of  59)  and  the  F3  generation 
(in  the  case  of  58)  of  the  cross  mut.formosa  X  mut.  latifolia  C.  All  of  the  plants  are  flat-leaved, 
and  when  grown  to  maturity  all  proved  to  be  f.  typica. 


TABLE  26 


Analysis  of  the  FZ  generation  resulting  from  self-pollination  off.  typica  plants  chosen  at  random 
from  the  FI  generation  (see  table  25)  of  the  cross  /.  typica  M  (homozygous)  X  /.  typica  C 
(a'pFF  X  ofiFF).  All  of  the  plants  are  fiat-leaved. 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

59 

No.    3 

ca.  400f 

3 

3 

0 

59 

No.    7 

ca.  600f 

2 

2 

0 

58 

No.    1 

l,664f 

9 

9 

0 

58 

No.    2 

l,500t 

20 

20 

0 

58 

No.    5 

l,647f 

280 

280 

0 

58 

No.  12 

l,423f 

230 

230 

0 

Total 

ca  7234 

544 

544 

o 

TABLE  27 
Analysis  of  the  FI  generation  of  the  cross  f.  typica  M  (heterozygous}  X  f.  typica  C  (a'fiFf  X  apFF). 


KEY 
NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TOTAL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

60 

225f 

9 

9 

0 

61 

247f 

7 

7 

0 

62 

318+f 

50 

50 

0 

Total   . 

790+ 

66 

68 

o 

The  pistillate  parent  belonged  to  the  F2  generation  of  the  cross  mut.  formosa  X  mut.  lati- 
folia C.  Each  of  the  cultures  contains  only  flat-leaved  plants.  Of  the  66  plants  grown  to  matu- 
rity, taken  hi  part  from  each  of  the  three  cultures,  65  proved  to  be  f .  typica,  and  the  remaining 
1  was  mut.  fallax. 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA 


39 


TABLE  28 

Analysis  of  the  F2  generation  resulting  from  self-pollination  of  f.  typica  plants  chosen  at  ran- 
dom from  the  F\  generation  (see  table  27}  of  the  cross  f.  typica  M  (heterozygous]  X  /.  typica  C 
(a'pF/X  c&FF). 


KEY 

NUMBER 

PARENT  PLANT 

SEEDS  PLANTED 

TO1AL  PLANTS 

FLAT-LEAVED 

REVOLUTE- 
LEAVED 

RATIO 

60 

No.    1 

ca.  l,200t 

839 

839 

0 

60 

No.    4 

ca.  l,300f 

887 

887 

0 

60 

No.    5 

ca.     700f 

239 

239 

0 

60 

No.    6 

ca.     900f 

487 

487 

0 

60 

No.    9 

ca.  l,700t 

1,066 

1,066 

0 

61 

No.    2 

675f 

399 

399 

0 

61 

No.    3 

ca.  l,100t 

465 

465 

0 

62 

No.    8 

ca.     550f 

109 

109 

0 

62 

No.    9 

ca.     800f 

80 

80 

0 

62 

No.  19 

ca.     400f 

52 

52 

0 

62 

No.  33 

ca.     700f 

48 

48 

0 

Total 

ca.  10,025 

4,671 

4,671 

o 

60 

No.    3 

l,011f 

286 

213 

73 

2.92:1 

60 

No.    8 

ca.  l,200f 

378 

308 

70 

4.40:1 

61 

No.    1 

773f 

109 

88 

21 

4.19:1 

61 

No.    6 

ca.  l,300f 

892 

698 

194 

3.60:1 

62 

No.  36 

ca.     600f 

20 

17 

3 

5.67:1 

61 

No.    4 

ca.  l,000f 

561 

470 

91 

5.16:1 

61 

No.    5 

ca.  l,500f 

1,128 

830 

298 

2.79:1 

Total 

ca.  7,384 

3,374  ' 

2,624 

750 

3.50:1 

Of  the  eighteen  progenies,  eleven  consist  entirely  of  flat-leaved  plants  and  seven  consist  of 
flat-leaved  and  revolute-leaved  plants  in  approximately  a  3:1  ratio.  The  ratio  11:7  does  not 
approach  as  closely  as  expected,  to  the  1 : 1  ratio  of  gametes  bearing  the  dominant  factor  to 
gametes  bearing  the  recessive  factor,  produced  by  the  heterozygous  pistillate  parent  of  the  cross. 


GENETICS  6:    Ja  1921 


40 


FRIEDA  COBB 


.23' 


02.  cjrj. 
"8  "8 


03.  CQ. 
88 


03. 

8 


o. 

II 


- 


«j 

II 


fQ  I  *N 

§  3S 

G,gs 


X  £»• 

8  8 


53-  x 

8  8 


4  x  I 

g         ^ 


H 


^       g 


8  X 

•-S,       ^ 


MENDELIAN  INHERITANCE  IN  OENOTHERA   PRATINCOLA 


41 


CQ.  CQ.          CQ; 
"8  "8          "8 


CQ.  oi       oa. 
"8  "8         "8 


CQ.    CQ.  CQ7 

88  8 


^ 


: 
« 


<     X 


-  X 


e 


1 


X  •£, 

- 


Ix  § 

8  8 


Ixl 

8  8 


H 


0 


x 


X 


u 

X« 
<o 

i 


GENETICS  6  :    Ja  1921 


42 


FRIEDA  COBB 


TABLE  30 

Ratios  of  fiat-leaved  to  revolute-leaved  plants  (given  in  terms  of  flat-leaved  plants  per  thousand  ger- 
minations) in  all  cultures  in  which  the  expectation  is  750,  assembled  and  classified  according  to 
percentage  of  germination. 


PERCENTAGE  OF  GERMINATION 

1-5 

5-10 

10-15 

15-20 

20-25 

25-30 

30-35 

35-40 

40-45 

45-50 

50-81 

627 

476 

611 

681 

635 

652 

667 

708 

702 

718 

736 

630 

567 

655 

682 

658 

677 

731 

743 

713 

727 

746 

639 

606 

678 

704 

678 

720 

745 

751 

729 

742 

772 

651 

649 

685 

707 

697 

742 

750 

769 

730 

780 

*0  Jj 

652 

667 

712 

711 

717 

745 

799 

808 

739 

838 

'o  ^_, 

667 

690 

725 

737 

726 

786 

815 

812 

0  'J3 

676 

709 

730 

748 

730 

800 

.S  £ 

676 

730 

743 

750 

732 

•!-s 

700 

739 

747 

771 

737 

a| 

706 

742 

754 

800 

744 

710 

742 

763 

744 

$  "*"* 

719 

743 

789 

756 

11 

727 

745 

789 

762 

*J   >. 

739 

747 

793 

772 

ll 

741 

750 

795 

782 

1  I 

742 

750 

804 

830 

1  §0 

750 

755 

808 

854 

•d*  *°  ^ 

765 

766 

825 

914 

>  ^  *M 

765 

806 

836 

jo  *o  ja 

766 

815 

*S  £  1 

778 

818 

•~  3  »S 

800 

897 

°  3  g 

808 

917 

-|  <u  S, 

816 

|  "5  4) 

* 

833 

850 

863 

869 

917 

Average  .  .  . 

744 

732 

750 

729 

748 

732 

751 

765 

726 

729 

774 

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